Appl Environ Microbiol, 2001 Sep, 67(9), 4365 - 71 Diversity and distribution in hypersaline microbial mats of bacteria related to Chloroflexus spp; Nubel U et al.; Filamentous bacteria containing bacteriochlorophylls c and a were enriched from hypersaline microbial mats . Based on phylogenetic analyses of 16S rRNA gene sequences, these organisms form a previously undescribed lineage distantly related to Chloroflexus spp . We developed and tested a set of PCR primers for the specific amplification of 16S rRNA genes from filamentous phototrophic bacteria within the kingdom of "green nonsulfur bacteria." PCR products recovered from microbial mats in a saltern in Guerrero Negro, Mexico, were subjected to cloning or denaturing gradient gel electrophoresis and then sequenced . We found evidence of a high diversity of bacteria related to Chloroflexus which exhibit different distributions along a gradient of salinity from 5.5 to 16%. Appl Environ Microbiol, 2001 Sep, 67(9), 4324 - 8 Mapping microbial biodiversity; Stoner DL et al.; We report the development of a prototype database that "maps" microbial diversity in the context of the geochemical and geological environment and geographic location . When it is fully implemented, scientists will be able to conduct database searches, construct maps containing the information of interest, download files, and enter data over the Internet. Appl Environ Microbiol, 2001 Sep, 67(9), 4233 - 41 Bacteriophage latent-period evolution as a response to resource availability; Abedon ST et al.; Bacteriophages (phages) modify microbial communities by lysing hosts, transferring genetic material, and effecting lysogenic conversion . To understand how natural communities are affected it is important to develop predictive models . Here we consider how variation between models--in eclipse period, latent period, adsorption constant, burst size, the handling of differences in host quantity and host quality, and in modeling strategy--can affect predictions . First we compare two published models of phage growth, which differ primarily in terms of how they model the kinetics of phage adsorption; one is a computer simulation and the other is an explicit calculation . At higher host quantities (approximately 10(8) cells/ml), both models closely predict experimentally determined phage population growth rates . At lower host quantities (10(7) cells/ml), the computer simulation continues to closely predict phage growth rates, but the explicit model does not . Next we concentrate on predictions of latent-period optima . A latent-period optimum is the latent period that maximizes the population growth of a specific phage growing in the presence of a specific quantity and quality of host cells . Both models predict similar latent-period optima at higher host densities (e.g., 17 min at 10(8) cells/ml) . At lower host densities, however, the computer simulation predicts latent-period optima that are much shorter than those suggested by explicit calculations (e.g., 90 versus 1,250 min at 10(5) cells/ml) . Finally, we consider the impact of host quality on phage latent-period evolution . By taking care to differentiate latent-period phenotypic plasticity from latent-period evolution, we argue that the impact of host quality on phage latent-period evolution may be relatively small. Burns, 2001 Sep, 27(6), 621 - 7 The use of silver coated dressings on donor site wounds: a prospective, controlled matched pair study; Innes ME et al.; Acticoat, a new silver-coated dressing, produces a moist healing environment along with the sustained release of ionic silver for improved microbial control . These properties suggest that Acticoat might be a useful donor site dressing . However, there are no human studies which assess Acticoat for this use . The purpose of this study was to compare the healing of human skin graft donor sites dressed with Acticoat, to the healing of those dressed with Allevyn, an occlusive moist-healing environment material, which is our standard donor site dressing . In burn patients who had undergone burn excision and grafting, identical side-by-side split thickness donor site wound pairs were dressed with Allevyn and Acticoat . Re-epithelialization was directly assessed daily by a single observer from post-operative day 6 onward, and by four independent observers who rated the extent of re-epithelialization by viewing standardized digital images of the wounds that had been obtained on post-operative days 6, 8, 10,and 12 . Donor sites were swabbed for bacterial culture on days 3, 6, and 9 . Subsequently, each study donor site scar was rated by a blinded observer using the Vancouver Scar Scale at 1, 2, and 3 months . Sixteen paired sites in 15 patients (3 female, 12 male) were studied . Donor sites dressed with Allevyn were >90% re-epithelialized at a mean of 9.1+/-1.6 days while donor sites dressed with Acticoat required a mean of 14.5+/-6.7 days to achieve >90% re-epithelialization (P=0.004) . The Allevyn sites had significantly greater estimated re-epithelialization at days 6, 8, 10 and 12 than the Acticoat sites based on the observations of the digital images . There were no significant differences in the incidence of positive bacterial cultures with either dressing at days 3, 6, and 9 . Donor sites dressed with Acticoat had significantly worse scars at 1 and 2 months but this difference resolved by 3 months . Our findings do not support the use of Acticoat as a skin graft donor site dressing. Appl Microbiol Biotechnol, 2001 Jun, 55(6), 787 - 93 Microbial sulfate reduction with acetate: process performance and composition of the bacterial communities in the reactor at different salinity levels; Muthumbi W et al.; Microbial sulfate reduction with acetate as carbon source and electron donor was investigated at salinity levels between 0.53 and 1.48% . The experiment was carried out in a 2.3-1 upflow anaerobic sludge blanket reactor inoculated with granular methanogenic sludge . A pH of 8.3, a temperature of 32 +/- 1 degrees C and a chemical oxygen demand (COD)/SO4(2-)-S ratio of 2 were maintained in the reactor throughout the experiment . Sulfate reduction and the composition of the dominant bacterial communities in the reactor were monitored . The results showed that a maximal conversion rate for SO4(2-)-S of 14 g l(-1) day(-1) and a conversion efficiency of more than 90% were obtained at a salinity level of 1.26-1.39% . A further increase in the salinity level led to reactor instability . Denaturant gradient gel electrophoresis of 16S rDNA fragments amplified by PCR from total bacterial DNA extracted from the inoculum and reactor sludge showed that salinity level had an impact on the composition of the bacterial communities in the reactor . However, no clear relationship was found between reactor performance and the composition of the dominant bacterial communities in the reactor. J Periodontol, 2001 Aug, 72(8), 1038 - 44 Regulation of cytokine production in human gingival fibroblasts following treatment with nicotine and lipopolysaccharide; Wendell KJ et al.; BACKGROUND: Patients who smoke are at increased risk for chronic periodontitis (CP) . Most studies suggest that the microbial flora in these patients is similar to that found in non-smoking CP patients . Thus, the increased risk for development of CP is not dependent on an altered microbial profile, but rather to some change in the host response to these periopathogens . There is evidence that human gingival fibroblasts (HGF) derived from diseased sites produce greater amounts of interleukin (IL)-6 and IL-8 in vitro than cells derived from healthy sites . This suggests that HGF subpopulations may be selected based upon the inflammatory milieu in which they reside . The hypothesis to be tested was that the combination of nicotine and lipopolysaccharide (LPS) could regulate HGF inflammatory mediator production . METHODS: HGF cell cultures were established from explants derived from 10 patients with CP . HGF cell cultures were stimulated with 1 mM, 1 microM, or 1 nM nicotine +/- Escherichia coli or Porphyromonas gingivalis LPS . At 12, 24, or 48-hour time points, the cells were counted and the supernatant was collected for subsequent IL-6 and IL-8 determination in an enzyme-linked immunosorbent assay . RESULTS: At the 24-hour time point, 1 nM nicotine stimulated IL-6 production compared to control (P=0.02) . E . coli LPS alone caused a 3- to 4-fold increase in IL-6 and IL-8 production, whereas P gingivalis LPS did not augment IL-6 or IL-8 . A synergistic effect upregulating IL-6 was observed with combined treatment of 1 mM nicotine and E . coli LPS or P gingivalis LPS at the 24-hour time point (P<0.0005 and P=0.002, respectively) . Similar effects were seen when IL-8 production was evaluated following HGF stimulation with high doses of nicotine and E . coli LPS or P gingivalis LPS . CONCLUSIONS: These results demonstrate that nicotine by itself can stimulate HGF IL-6 and IL-8 production . Moreover, the combination of high doses of nicotine and either E . coli or P gingivalis LPS can synergistically upregulate cytokine production . These findings support the hypothesis that a proinflammatory fibroblast phenotype may be elicited in an environment enriched with bacterial LPS and nicotine. Curr Genet, 2001 Jul, 39(5-6), 365 - 70 Highly efficient expression of rabbit neutrophil peptide-1 gene in Chlorella ellipsoidea cells; Chen Y et al.; A highly efficient system was developed for the expression of foreign genes in Chlorella ellipsoidea cells . The effect of five promoters on the expression efficiency of beta-glucuronidase (GUS) gene was evaluated by transient expression of the UidA gene . Among these promoters, Ubiquitin-omega was found to be the most efficient and was selected to drive the expression of foreign genes in Chlorella cells . A gene encoding the mature rabbit neutrophil peptide-1 (NP-1) was introduced into the cells . Integration of the gene for NP-1 into the Chlorella genome was confirmed by PCR and Southern blot analysis . In, vitro anti-microbial testes demonstrated the expression of biologically active NP-1 by the transgenic Chlorella cells. Structure (Camb), 2001 Apr 4, 9(4), 311 - 9 Crystal structures of a novel ferric reductase from the hyperthermophilic archaeon Archaeoglobus fulgidus and its complex with NADP+; Chiu HJ et al.; BACKGROUND: Studies performed within the last decade have indicated that microbial reduction of Fe(III) to Fe(II) is a biologically significant process . The ferric reductase (FeR) from Archaeoglobus fulgidus is the first reported archaeal ferric reductase and it catalyzes the flavin-mediated reduction of ferric iron complexes using NAD(P)H as the electron donor . Based on its catalytic activity, the A . fulgidus FeR resembles the bacterial and eukaryotic assimilatory type of ferric reductases . However, the high cellular abundance of the A . fulgidus FeR (approximately 0.75% of the total soluble protein) suggests a catabolic role for this enzyme as the terminal electron acceptor in a ferric iron-based respiratory pathway {1} . RESULTS: The crystal structure of recombinant A . fulgidus FeR containing a bound FMN has been solved at 1.5 A resolution by multiple isomorphous replacement/ anomalous diffraction (MIRAS) phasing methods, and the NADP+- bound complex of FeR was subsequently determined at 1.65 A resolution . FeR consists of a dimer of two identical subunits, although only one subunit has been observed to bind the redox cofactors . Each subunit is organized around a six-stranded antiparallel beta barrel that is homologous to the FMN binding protein from Desulfovibrio vulgaris . This fold has been shown to be related to a circularly permuted version of the flavin binding domain of the ferredoxin reductase superfamily . The A . fulgidus ferric reductase is further distinguished from the ferredoxin reductase superfamily by the absence of a Rossmann fold domain that is used to bind the NAD(P)H . Instead, FeR uses its single domain to provide both the flavin and the NAD(P)H binding sites . Potential binding sites for ferric iron complexes are identified near the cofactor binding sites . CONCLUSIONS: The work described here details the structures of the enzyme-FMN, enzyme-FMN-NADP+, and possibly the enzyme-FMN-iron intermediates that are present during the reaction mechanism . This structural information helps identify roles for specific residues during the reduction of ferric iron complexes by the A . fulgidus FeR. FEMS Microbiol Rev, 2001 Aug, 25(4), 455 - 501 Classification and phylogeny of hydrogenases; Vignais PM et al.; Hydrogenases (H2ases) catalyze the reversible oxidation of molecular hydrogen and play a central role in microbial energy metabolism . Most of these enzymes are found in Archaea and Bacteria, but a few are present in Eucarya as well . They can be distributed into three classes: the {Fe}-H2ases, the {NiFe}-H2ases, and the metal-free H2ases . The vast majority of known H2ases belong to the first two classes, and over 100 of these enzymes have been characterized genetically and/or biochemically . Compelling evidence from sequences and structures indicates that the {NiFe}- and {Fe}-H2ases are phylogenetically distinct classes of proteins . The catalytic core of the {NiFe}-H2ases is a heterodimeric protein, although additional subunits are present in many of these enzymes . Functional classes of {NiFe}-H2ases have been defined, and they are consistent with categories defined by sequence similarity of the catalytic subunits . The catalytic core of the {Fe}-H2ases is a ca . 350-residue domain that accommodates the active site (H-cluster) . A few monomeric {Fe}-H2ases are barely larger than the H-cluster domain . Many others are monomeric as well, but possess additional domains that contain redox centers, mostly iron-sulfur . Some {Fe}-H2ases are oligomeric . The modular structure of H2ases is strikingly illustrated in recently unveiled sequences and structures . It is also remarkable that most of the accessory domains and subunits of H2ases have counterparts in other redox complexes, in particular NADH-ubiquinone oxidoreductase (Complex I) of respiratory chains . Microbial genome sequences are bringing forth a significant body of additional H2ase sequence data and contribute to the understanding of H2ase distribution and evolution . Altogether, the available data suggest that {Fe}-H2ases are restricted to Bacteria and Eucarya, while {NiFe}-H2ases, with one possible exception, seem to be present only in Archaea and Bacteria . H2ase processing and maturation involve the products of several genes which have been identified and are currently being characterized in the case of the {NiFe}-H2ases . In contrast, near to nothing is known regarding the maturation of the {Fe}-H2ases . Inspection of the currently available genome sequences suggests that the {NiFe}-H2ase maturation proteins have no similar counterparts in the genomes of organisms possessing {Fe}-H2ases only . This observation, if confirmed, would be consistent with the phylogenetic distinctiveness of the two classes of H2ases . Sequence alignments of catalytic subunits of H2ases have been implemented to construct phylogenetic trees that were found to be consistent, in the main, with trees derived from other data . On the basis of the comparisons performed and discussed here, proposals are made to simplify and rationalize the nomenclature of H2ase-encoding genes. FEMS Microbiol Rev, 2001 Aug, 25(4), 425 - 35 Genomic style of proteins: concepts, methods and analyses of ribosomal proteins from 16 microbial species; Radomski JP et al.; We have introduced the concept of genomic 'style' of proteins . By style we understand those properties of a large set of proteins which are specific to the genome of one species (species primary-self) and different from the genome of another species (species contrasted-self) . To characterise the style, we took advantage of the frequencies of amino acids and dipeptides present in non-identical segments of the complete set of orthologous ribosomal proteins encoded by 16 microbial species . We confirm the dependence of the overall amino acid composition on the genomic (G+C) content, and introduce a rectification procedure making it possible to extricate appropriate species-specific characteristics, which are no longer related to this content . The rectified frequencies are used to calculate inter-species distance matrices, and to build genomic evolutionary trees . Remarkably, the phylograms derived from the frequencies of non-identical residues in proteins closely resemble the classical phylograms based upon the conservation of identical residues in ribosomal RNAs . We believe that the concept of genomic style of proteins can be a useful tool for the study of evolution. Yakugaku Zasshi, 2001 Aug, 121(8), 593 - 600 {Efficient gene delivery into dendritic cells by fiber-mutant adenovirus vectors}; Okada N; Dendritic cells (DC) are professional antigen-presenting cells with a key function in the immune system as initiators of T-cell responses against microbial pathogens and tumors . Therefore, the immunization using DC loaded with tumor-associated antigens is potential to represent a powerful method of inducing anti-tumor immunity . Recent studies have demonstrated the usefulness of DC genetically modified by adenovirus vectors (Ad) to immunotherapy, while sufficient gene transduction into DC is required for high doses of Ad . Entry of Ad into target cells occurs by serial two steps: the binding of Ad-fiber knob to Coxsackie-adenovirus receptor (CAR) on the cell surface, and the subsequent interaction between Arg-Gly-Asp (RGD) motif located in Ad-penton base and alpha v-integrins . The reverse transcription-polymerase chain reaction analysis revealed that the relative resistance of DC to Ad-mediated gene transfer was due to the absence of CAR expression, and that DC expressed adequate alpha v-integrins . Therefore, we investigated whether fiber-mutant Ad (FM-Ad) containing the RGD sequence in the fiber knob can efficiently transduce and express high levels of the foreign gene into DC . The gene delivery by FM-Ad was more efficient than that by conventional Ad in both murine DC lines and normal human DC . Furthermore, both antigen presentations via major histocompatibility complex class I molecules and in vivo antigen-specific cytotoxic T lymphocyte induction by DC transduced with antigen gene by FM-Ad were superior to those by DC applied with conventional AD . We propose that alpha v-integrin-targeted FM-Ad is a very powerful tool to implement DC-based vaccination strategies. J Endotoxin Res, 2000, 6(6), 453 - 7 Molecular mechanisms of NF-kappaB activation induced by bacterial lipopolysaccharide through Toll-like receptors; Zhang G et al.; Septic shock, caused by exaggerated host responses to various microbial products typified by lipopolysaccharide (LPS), remains the leading cause of death in trauma patients . Gaining insight into the nature of host interactions with LPS will certainly facilitate attempts to develop effective anti-sepsis drugs . Tremendous progress has been made during the past few years in understanding the mechanisms of pathogen-induced host responses . Toll-like receptor (TLR) 4 and 2 have been implicated as major receptors for signaling initiated by LPS and many other microbial products following their binding to CD14 . In addition, many signaling intermediates involved in LPS-induced cell activation, particularly activation of the transcription factor NF-kappaB, have been identified and characterized . Further investigations with these molecules will certainly reward us with more effective therapeutic drugs to treat septic shock as well as many other inflammatory and infectious disorders. Early Hum Dev, 2001 Oct, 65(1), 11 - 9 The characterization of superoxide production of human neonatal neutrophil; Komatsu H et al.; To assess the role of neutrophil in neonatal host defense against microbial infection, we characterized the superoxide anion (O(2-)) production of neonatal neutrophil on a biochemical basis . After taking an appropriate informed consent, neutrophils were obtained from cord blood immediately after transvaginal delivery and divided into two groups: the Preterm group, 15 neonates (27-36 weeks' gestation) and the Term group, 15 neonates (37-41 weeks' gestation) . Eleven healthy adults served as controls in the Adult group . The value of N-formyl-methionyl-leucyl-phenylalanin (fMLP)-induced O(2-) production activity of neutrophils in the Preterm group using chemiluminescence assay was significantly lower than those values in both the Term and Adult groups (5.77+/-0.53x10(6) vs . 11.1+/-0.94x10(6) and 10.7+/-0.63x10(6) cpm; mean+/-S.E.M., p<0.05) . In phorbol 12-myristate 13-acetate (PMA)-stimulation, the values of O(2-) production activity of neutrophils in both the Preterm and Term groups were significantly lower than that in the Adult group (13.0+/-1.66x10(6) and 18.0+/-1.44x10(6) vs . 27.3+/-1.45x10(6) cpm, p<0.05) . Scatchard analysis of {(3)H}fMLP binding to neutrophil demonstrated a two-receptor model in each group, and the number of high-affinity receptors per neutrophil in the Preterm group was significantly lower than those in other groups (p<0.05) . However, cord blood levels of proinflammatory cytokines, such as interleukin (IL)-6, -8, and tumor necrosis factor-alpha (TNF-alpha) did not differ in either neonatal group . These results indicated that the fMLP-induced O(2-)production activity of neutrophils in the term neonates was enhanced at the level of the receptor and suggested that this enhanced production contribute to the neonatal host defense against microbial infection. J Nat Prod, 2001 Aug, 64(8), 1098 - 9 Microbial transformation of pyrethrosin; Galal AM; Microbial transformation of the germacranolide pyrethrosin (1) using Rhizopus nigricans NRRL 1477 has resulted in the isolation of 6 alpha-acetoxy-1 beta,4 alpha-dihydroxy-5,7 alpha H,8 beta H-eudesm-11 beta,13-dihydro-8,12-olide (5), a new eudesmanolide-type metabolite, in addition to the previously reported eudesmanolides: 2, 3, 4, and 6 . The structure elucidation of these metabolites was based primarily on 1D and 2D NMR analyses . The isolated metabolites exhibited cytotoxic, antifungal, and antiprotozoal activities. Am J Physiol Gastrointest Liver Physiol, 2001 Sep, 281(3), G764 - 78 Helicobacter-induced inflammatory bowel disease in IL-10- and T cell-deficient mice; Burich A et al.; Inflammatory bowel disease (IBD) is thought to result from a dysregulated mucosal immune response to luminal microbial antigens, with T lymphocytes mediating the colonic pathology . Infection with Helicobacter spp has been reported to cause IBD in immunodeficient mice, some of which lack T lymphocytes . To further understand the role of T cells and microbial antigens in triggering IBD, we infected interleukin (IL)-10(-/-), recombinase-activating gene (Rag)1(-/-), T-cell receptor (TCR)-alpha(-/-), TCR-beta(-/-), and wild-type mice with Helicobacter hepaticus or Helicobacter bilis and compared the histopathological IBD phenotype . IL-10(-/-) mice developed severe diffuse IBD with either H . bilis or H . hepaticus, whereas Rag1(-/-), TCR-alpha(-/-), TCR-beta(-/-), and wild-type mice showed different susceptibilities to Helicobacter spp infection . Proinflammatory cytokine mRNA expression was increased in the colons of Helicobacter-infected IL-10(-/-) and TCR-alpha(-/-) mice with IBD . These results confirm and extend the role of Helicobacter as a useful tool for investigating microbial-induced IBD and show the importance, but not strict dependence, of T cells in the development of bacterial-induced IBD. Bioseparation, 2000, 9(6), 351 - 7 Sub-micron particle manipulation in an ultrasonic standing wave: applications in detection of clinically important biomolecules; Sobanski MA et al.; Separation of particles from the suspending phase is of interest, among others, to clinical analysts . A system that enables manipulation of sub-micron sized particles in suspensions of analytical scale volume (10-50 microl) using a non-cavitating ultrasonic standing wave is described . Particle suspensions, contained in glass capillary tubes of 1-2 mm internal dimension, are treated on the axis of a tubular transducer generating a radial standing wave field at 4.5 MHz . Microparticles (of average diameter range 0.3-10 microm) suspended in buffer are concentrated within seconds at preferred regions separated by submillimetre distances . Concentration of suspended latex particles was inhibited in solutions containing protein at levels similar to those occurring in clinical specimens when the suspensions were sonicated in capillaries of circular cross-section . This effect was associated with acoustic streaming of the suspending fluid . Silica microparticles (more dense and less compressible than latex) could be concentrated in the presence of streaming . Latex particles concentrated readily in square cross-section capillaries where no streaming was observed . With sub-micron particles, the geometry of the sample chamber, the suspending phase composition and the size, density and compressibility of the microparticles all influence particle manipulation . The radial standing wave system has been used to enhance agglutination of antibody-coated latex microparticles in the presence of antigen allowing rapid and highly sensitive detection of clinically important biomolecules . The sensitivity of conventional diagnostic tests for microbial antigen has been improved by application of ultrasound and clinical utility has been demonstrated, in particular, for detection of meningitis-causing bacteria. J Anim Sci, 2001 Aug, 79(8), 2224 - 32 The effects of degradable and undegradable intake protein on the performance of lactating first-calf heifers; Anderson LP et al.; Two 60-d experiments were conducted to evaluate the effects of supplementing degradable (DIP) and(or) undegradable (UIP) intake protein on the performance of lactating first-calf heifers . Diets were formulated to meet the requirements for either DIP, metabolizable protein (MP), or both when diets contained low-quality grass hay and an efficiency of microbial protein synthesis estimate of 10% . In Exp . 1, 32 individually fed first-calf heifers (avg 395 kg) were allotted to a 2 x 2 factorial arrangement of treatments (main effects of DIP, MP, and DIP x MP interaction) 1 d after calving . Cows consumed a basal diet of chopped crested wheat grass hay (4.3% CP, 67% DIP) ad libitum . Supplemental DIP and UIP were supplied by varying the ratios of soybean meal (75% DIP) and a heat-treated, protected soybean meal (70% UIP) . Cow weight gain was better (P < 0.01) when adequate DIP was supplied than when DIP was deficient . However, calf weight gain was not increased by supplementing the cow with DIP . Supplemental UIP did not (P > 0.40) improve cow or calf weight gain . Blood urea N levels were higher (P < 0.01) for cows receiving supplemental DIP and UIP . However, milk production estimates were similar among treatments, as were digestibilities of OM and ADF . Nitrogen digestibility was greater when supplemental DIP was fed, but providing additional UIP did not (P = 0.15) change N digestibilities . Experiment 2 evaluated similar supplements using the same experimental design to determine changes in cow and calf weight gain, body condition score, and pregnancy rate . Seventy-two first-calf heifers (avg 441 kg) were allotted to supplement treatments 1 d after calving and were fed grass hay (5% CP, 53% DIP, 10% microbial efficiency) for ad libitum consumption for 60 d . Supplements were individually fed three times/week . Varying the ratios of soybean meal, heat-treated soybean meal, and corn gluten meal provided additional DIP and UIP . Unlike in Exp . 1, supplemental UIP improved (P < 0.05) cow weight gain . Calves from dams supplemented with DIP gained 5 kg more weight after 60 d than calves from dams deficient in DIP . Pregnancy rates in the fall were similar (P = 0.90) among treatments . These data suggest that DIP was more limiting in Exp . 1 than was UIP . Supplementing UIP in Exp . 2 improved cow weight gains but did not improve calf gains . Data suggest that the efficiency of microbial protein synthesis for this forage-based diet was probably less than 10%. Adv Drug Deliv Rev, 2001 Sep 23, 51(1-3), 143 - 7 Bacteria-derived particles as adjuvants for non-replicating nasal vaccines; Haneberg B et al.; In attempts to mimic natural infections, vaccines consisting of microbial particles may be delivered directly to mucosal surfaces . In this way, the mucosal as well as the systemic immune systems can be activated . Even non-living particles of bacterial origin have been shown to elicit strong immune responses when administered intranasally . However, some particles such as formalin-inactivated influenza virus may need a mucosal adjuvant to be effective . The bacteria-derived particles seem to possess such an adjuvant activity when mixed with and given intranasally with the less immunogenic killed virus . Possibly, the bacterial particles facilitate uptake of the virus through the mucosal membranes, although an additional influence on the immune response to the virus might be mediated in the lymphoid tissue below the mucosal surface . Bacteria-derived particles in nasal vaccines may thus serve as an alternative adjuvant to derivatives of cholera toxin or the heat-labile toxin from E . coli. Curr Biol, 2001 Jun 5, 11(11), R440 - 2 Evolution: towards a genetical theory of adaptation; Travisano M; The population genetic basis for adaptation has remained obscure despite a longstanding body of theory . Microbial selection experiments are beginning to provide some answers. Int Immunopharmacol, 2001 Aug, 1(8), 1605 - 14 Bacterial DNA does not increase serum corticosterone concentration or prevent increases induced by other stimuli; Myers LP et al.; Bacterial DNA containing unmethylated CpG motifs (CpG DNA) and other microbial molecules such as lipopolysaccharide (LPS) have a broad range of immune stimulatory effects, which may include many shared cell signaling pathways leading to enhanced cytokine production . Some cytokines activate the hypothalamic-pituitary-adrenal (HPA) axis, and their production is downregulated by products of the HPA axis (glucocorticoids) . Because such interactions have practical implications in the clinical use of CpG DNA, the present study was done to examine the effects of CpG DNA and LPS on serum corticosterone concentrations . In contrast to LPS, administration of CpG DNA (DNA from Escherichia coli) (30-300 microg) alone did not significantly increase serum corticosterone concentrations 1 or 4 h after administration . Administration of CpG DNA to mice prior to LPS caused a synergistic increase in serum tumor necrosis factor-alpha (TNF-alpha), indicative of an immune stimulatory effect . LPS and TNF-alpha, however, induced similar levels of corticosterone with or without concomitant CpG DNA . Increasing doses of LPS caused peak corticosterone levels similar to those induced by LPS in combination with CpG DNA . Exogenous TNF-alpha administered in vivo induced comparable concentrations of corticosterone with or without CpG DNA . An alternative stressor (restraint) yielded similar levels of corticosterone with or without CpG DNA . These results indicate that CpG DNA does not induce corticosterone release or alter its release by other stimuli, indicating biologically important differences in its immune effect compared to those of LPS, and possibly reduced toxicity. Braz J Biol, 2001 May, 61(2), 277 - 86 Microbial respiration and chemical composition of different sediment fractions in waterbodies of the upper Paraná River floodplain, Brazil; Thomaz SM et al.; Four size fractions of the sediment of six environments of the upper Parana River floodplain were analyzed for carbon, nitrogen, and phosphorus contents and microbial respiration (oxygen consumption) . Particle size did not affect nitrogen and phosphorus content or microbial activity, but did affect carbon content (F = 4.274, df = 3; 20, p = 0.020) . The carbon concentration of ultra-fine particles was significantly lower than that of other sizes of sediment particles . Microbial respiration values were well predicted by sediment chemical composition, as shown by multiple regression (microbial respiration = -0.39 - 0.210C + 0.108N + 0.796P; F = 7.0495, p = 0.0022) . However, phosphorus was the element which best explained the microbial respiration (partial coefficient = 0.796, p = 0.0039, n = 23) . Considering that i) phosphorus was the best predictor of microbial respiration; ii) phosphorus is trapped in the series of reservoirs located upstream from the section of the floodplain studied; and iii) microbial respiration is a measure of decomposition rates and nutrient cycling, we hypothesize that the long-term accumulation of litter detritus and reduction of nutrient cycling in environments of the upper Parana River floodplain are probable impacts of this decrease in phosphorus caused by the upstream reservoirs. Trends Biotechnol, 2001 Sep, 19(9), 340 - 8 The biotechnological control of pitch in paper pulp manufacturing; Gutierrez A et al.; At present, microbial and enzymatic preparations for the control of triglyceride-containing pitch deposits during the manufacture of mechanical and sulfite paper is commercially available . However, biotechnological products for pitch control in other pulping processes, such as alkaline pulping, are under development . These products include new fungi for the removal of steroids involved in pitch deposit formation in chlorine-free pulps, to be used as a biological pretreatment of wood before pulping . Simultaneously, tailor-made enzymes are being produced using protein-engineering techniques, enabling the specific removal of pitch contaminant compounds from paper pulp. Ann Occup Hyg, 2001 Aug, 45(6), 421 - 7 Sampling and detection of Legionella pneumophila aerosols generated from an industrial cooling tower; Ishimatsu S et al.; Cooling tower water has frequently been cited as a source of infection in outbreaks of Legionnaires' disease . However, there have been few reports on the presence of legionellae in aerosols from cooling towers . This paper describes our use of an impinger or a six-stage microbial impactor for detecting legionellae in air around a cooling tower contaminated with L . pneumophila (1.2+/-0.3x10(5) CFU/100 ml) . Phosphate-buffered saline, Page's saline, 2% yeast extract solution and buffered yeast extract (BYE) broth were tested to evaluate their collection efficiency . These solutions were compared in laboratory experiments using an aerosol of L . pneumophila serogroup (SG) 1 . Because BYE broth was the most efficient and storable collecting fluid among them, it was used for outdoor air sampling . In the outdoor air sampling, aerosolized L . pneumophila SG 6 was detected in the air around the cooling tower by the impinger (0.09 CFU/l . air) . No legionellae were detected by the impactor with Legionella-selective agar plates (WYOalpha) because the plates were overgrown with fungi . Repetitive element PCR (rep-PCR) and arbitrarily primed PCR (AP-PCR) were employed to assess the epidemiological relationship among Legionella isolates from the air sample and the cooling tower water samples . L . pneumophila SG 6 isolated from the aerosols produced rep-PCR and AP-PCR fingerprints identical to those of L . pneumophila SG 6 strains from the cooling tower water, suggesting that the bacterium was aerosolized from the cooling tower. J Agric Food Chem, 2001 Aug, 49(8), 3718 - 24 Improvement of malt modification by use of Rhizopus VII as starter culture; Noots I et al.; The development of a selected starter culture on malting barley and its effects on malt quality aspects were studied . Application of Rhizopus sporangiospores in a malting process resulted in increased beta-glucanase and xylanase contents of the malting barley and improved starchy endosperm cell-wall degradation . Activation of the sporangiospores and optimization of the inoculation procedure led to a further increase in enzyme levels and to larger and more consistent impacts on cell-wall modification . Whereas the main effect of the starter culture on beta-glucan degradation was observed during malting, a further decrease in beta-glucan during mashing suggests that the microbial enzymes that survived the kilning step were active during mashing . Other quality aspects that were influenced by the starter culture activity were protein modification, wort color, and wort pH . The level of microbial enzymes produced was related to the amount of barley kernels infected with the starter culture. Biochemistry, 2001 Aug 28, 40(34), 10371 - 81 Transient-state and steady-state kinetic studies of the mechanism of NADH-dependent aldehyde reduction catalyzed by xylose reductase from the yeast Candida tenuis; Nidetzky B et al.; Microbial xylose reductase, a representative aldo-keto reductase of primary sugar metabolism, catalyzes the NAD(P)H-dependent reduction of D-xylose with a turnover number approximately 100 times that of human aldose reductase for the same reaction . To determine the mechanistic basis for that physiologically relevant difference and pinpoint features that are unique to the microbial enzyme among other aldo/keto reductases, we carried out stopped-flow studies with wild-type xylose reductase from the yeast Candida tenuis . Analysis of transient kinetic data for binding of NAD(+) and NADH, and reduction of D-xylose and oxidation of xylitol at pH 7.0 and 25 degrees C provided estimates of rate constants for the following mechanism: E + NADH right arrow over left arrow E.NADH right arrow over left arrow E.NADH + D-xylose right arrow over left arrow E.NADH.D-xylose right arrow over left arrow E.NAD(+).xylitol right arrow over left arrow E.NAD(+) right arrow over left arrow E.NAD(+) right arrow over left arrow E + NAD(+) . The net rate constant of dissociation of NAD(+) is approximately 90% rate limiting for k(cat) of D-xylose reduction . It is controlled by the conformational change which precedes nucleotide release and whose rate constant of 40 s(-)(1) is 200 times that of completely rate-limiting E.NADP(+) --> E.NADP(+) step in aldehyde reduction catalyzed by human aldose reductase {Grimshaw, C . E., et al . (1995) Biochemistry 34, 14356-14365} . Hydride transfer from NADH occurs with a rate constant of approximately 170 s(-1) . In reverse reaction, the E.NADH --> E.NADH step takes place with a rate constant of 15 s(-1), and the rate constant of ternary-complex interconversion (3.8 s(-1)) largely determines xylitol turnover (0.9 s(-1)) . The bound-state equilibrium constant for C . tenuis xylose reductase is estimated to be approximately 45 (=170/3.8), thus greatly favoring aldehyde reduction . Formation of productive complexes, E.NAD(+) and E.NADH, leads to a 7- and 9-fold decrease of dissociation constants of initial binary complexes, respectively, demonstrating that 12-fold differential binding of NADH (K(i) = 16 microM) vs NAD(+) (K(i) = 195 microM) chiefly reflects difference in stabilities of E.NADH and E.NAD(+) . Primary deuterium isotope effects on k(cat) and k(cat)/K(xylose) were, respectively, 1.55 +/- 0.09 and 2.09 +/- 0.31 in H(2)O, and 1.26 +/- 0.06 and 1.58 +/- 0.17 in D(2)O . No deuterium solvent isotope effect on k(cat)/K(xylose) was observed . When deuteration of coenzyme selectively slowed the hydride transfer step, (D)()2(O)(k(cat)/K(xylose)) was inverse (0.89 +/- 0.14) . The isotope effect data suggest a chemical mechanism of carbonyl reduction by xylose reductase in which transfer of hydride ion is a partially rate-limiting step and precedes the proton-transfer step. Chemosphere, 2001 Aug, 44(5), 1265 - 71 Fate of pyrene in contaminated soil amended with alternate electron acceptors; Nieman JK et al.; Creosote-contaminated soil samples from the Libby Ground Water Contamination Superfund Site in Libby, MT, were amended with the potential alternate electron acceptors (AEA) nitrate (KNO3), manganese oxide (MnO2), and amorphous iron oxyhydroxide (FeOOH) and incubated at low oxygen tensions (0-6% O2) . The fate of 14C-pyrene was evaluated with respect to the different soil amendments . The fate of 14C from the radiolabeled pyrene with regard to mineralization and bound residue formation within soil humic fractions was not significantly different from controls for the iron and manganese amended soils . Nitrate amendments appeared to stimulate 14C-pyrene mineralization at a level of 170 mg NO3-N kg(-1), and inhibit mineralization at 340 mg NO3-N kg(-1) . The stimulatory effect did not appear to be the result of nitrate serving as an electron acceptor . Although AEA amendments did not significantly affect the rate or extent of 14C-pyrene mineralization, results of oxygen-deprived incubations (purged with N2) indicate that AEA may be utilized by the microbial community in the unsaturated contaminated soil system. Curr Drug Metab, 2001 Sep, 2(3), 215 - 43 Mechanism-based inactivators as probes of cytochrome P450 structure and function; Kent UM et al.; The cytochromes P450 superfamily of enzymes is a group of hemeproteins that catalyze the metabolism of an extensive series of compounds including drugs, chemical carcinogens, fatty acids, and steroids . They oxidize substrates ranging in size from ethylene to cyclosporin . Although significant efforts have been made to obtain structural information on the active sites of the microbial P450s, relatively little is currently known regarding the identities of the critical amino acid residues in the P450 active sites that are involved in substrate binding and catalysis . Since information on the crystal structures of the eukaryotic P450s has been relatively limited, investigators have used a variety of other techniques in attempts to elucide the structural features that play a role in the catalytic properties and substrate specificity at the enzyme active site . These include site-directed mutagenesis, natural mutations, homology modeling, mapping with aryl-iron complexes, affinity and photoaffinity labeling, and mechanism-based inactivators . A variety of different mechanism-based inactivators have proven to be useful in identifiying active site amino acid residues involved in substrate binding and catalysis . In this review we present a sampling of the types of studies that can be conducted using mechanism-based inactivators and highlight studies with several classes of compounds including acetylenes, isothiocyanates, xanthates, aminobenzotriazoles, phencyclidine, and furanocoumarins . Labeled peptides isolated from the inactivated proteins have been analyzed by N-terminal amino acid sequencing in conjunction with mass spectrometry to determine the sites of covalent modification . Mechanistic studies aimed at identifying the basis for the inactivation following adduct formation are also presented. Chemosphere, 2001 Sep, 44(6), 1339 - 46 Iron-mediated reactions of polychlorinated biphenyls in electrochemical peroxidation process (ECP); Arienzo M et al.; A study was conducted to explore some of the basic processes of polychlorinated biphenyl (PCB) destruction by a new technology termed electrochemical peroxidation process (ECP) . ECP represents an enhancement of the classic Fenton reaction (H2O2 + Fe2+) in which iron is electrochemically generated by steel electrodes . Focus was on the extent of adsorption of a mixture of Aroclor 1248 on steel electrodes in comparison to iron filings . Commercially available zero-valent iron filings rapidly adsorbed PCBs from an aqueous solution of Aroclor 1248 . Within 4 h, all the PCBs were adsorbed at 1%, 5%, and 10% Fe0 (w/v) concentrations . Little difference in adsorption was found between acidic (2.3) and unamended solutions (pH 5.5), even though significant differences in iron oxidation state and Fe2+ concentrations were measured in solution . PCB adsorption also occurs on steel electrodes regardless of the pH or electric current applied (AC or DC), suggesting the combination of oxidizing (free radical-mediated reactions) and reducing (dechlorination reactions) iron-mediated degradation pathways may be possible . Extraction of the iron powder after 48 h of contact time yielded the progressive recovery of biphenyl with increasing Fe mass(from 0.4% to 3.5%) and changes of the PCB congener-specific pattern as a consequence of dechlorination . A variety of daughter congeners similar to those accumulated during anaerobic microbial dechlorination of Aroclor 1248 in contaminated sediments indicate preferential removal of meta- and para-chlorines. J Food Prot, 2001 Aug, 64(8), 1128 - 33 Response surface modeling for the inactivation of Escherichia coli O157:H7 on green peppers (Capsicum annuum L.) by chlorine dioxide gas treatments; Han Y et al.; The effects of chlorine dioxide (ClO2) gas concentration (0.1 to 0.5 mg/liter), relative humidity (RH) (55 to 95%), treatment time (7 to 135 min), and temperature (5 to 25 degrees C) on inactivation of Escherichia coli O157:H7 on green peppers were studied using response surface methods . A four-factor, central, composite, rotatable design was used . The microbial log reduction was measured as a response . A direct membrane-surface-plating method with tryptic soy agar and sorbitol MacConkey agar was used to resuscitate and enumerate ClO2-treated E . coli O157:H7 cells . The statistical analysis and the predictive model developed in this study suggest that ClO2 gas concentration, treatment time, RH, and temperature all significantly (P < 0.01) increased the inactivation of E . coli O157:H7 . ClO2 gas concentration was the most important factor, whereas temperature was the least significant . The interaction between ClO2 gas concentration and RH indicated a synergistic effect . The predictive model was validated, and it could be used to determine effective ClO2 gas treatments to achieve a 5-log reduction of E . coli O157:H7 on green peppers. J Microencapsul, 2001 Sep-Oct, 18(5), 627 - 36 PLGA microsphere bioburden evaluation for radiosterilization dose selection; Geze A et al.; The aim of this study was to determine the bioburden of PLGA microspheres produced by the solvent emulsion/extraction process as a means of determining an appropriate gamma-irradiation dose for sterilization . Bioburden was evaluated on the basis of ISO specifications . The analysis of initial microbial contamination was performed on blank microspheres, prepared by a non-aseptic laboratory scale process . A mean bioburden of 36.04 CFU (colony forming units)/110 mg microspheres was determined . Most of the detected germs originated from human commensal flora . According to the ISO dose-selection method, a gamma-irradiation dose of 19.6 kGy was found sufficient to ensure a sterility level of 10(-6) . The effect of the selected irradiation dose on both the molecular weight of the polymer and the kinetics of 5-fluorouracil drug release from the microspheres was compared to the European Pharmacopeia recommended irradiation dose (25 kGy) . This 20% reduced dose showed a lower extent of molecular weight reduction of PLGA and a better control of 5-FU release from microparticles . This can be related to reduce polymer radiation damage. Int J Circumpolar Health, 2001 Apr, 60(2), 150 - 6 Moulds, moisture and microbial contamination of First Nations housing in British Columbia, Canada; Lawrence R et al.; This paper reviews the difficulties experienced with mould growth in First Nations homes in British Columbia and to describe the team approach used in dealing with this problem . Humid, damp conditions promote the growth of bacteria, moulds, and dust mites . These organisms contribute to poor air quality and causes serious health problems . There is increasing evidence indicating an association between mould, particularly toxigenic moulds, and some diseases, notably asthma . These health problems usually improve when families are relocated to more suitable accommodation . Those particularly at risk include atopic, immunocompromised, very young and elderly individuals and those with chronic health conditions . Our experience suggests that substandard housing is a major contributor to poor health in First Nations communities. Huan Jing Ke Xue, 2001 May, 22(3), 97 - 9 {Microbial degradation of polychlorinated dibenzo-p-dioxins}; Du X et al.; PCDDs-degrading bacterial strains were isolated from soil and oxic-sediments polluted by PCDDs . One of them was identified as Pseudomonas sp . EE41 . They are capable of growing on and degrade mono- and di-chlorinated dibenzo-p-dioxins as a sole carbon source . The biodegradability of TrCDD and TCDD can be enhanced through primary nutrient of co-metabolism of o-CDB, thus, 1,2,3-TrCDD and 2,3,7,8-TCDD were degraded by 33% (at the concentration of 1.2 mg/L, within 3 weeks) and 37.8% (at the concentration of 0.1 mg/L, within 3 weeks) respectively . Most highly chlorinated dibenzo-p-dioxins (P-CDD, H6-, H7-CDD and OCDD) tested in this study were accumulated in bacterial cells, but could not be degraded. Nature, 2001 Aug 16, 412(6848), 701 - 5 Structural mimicry in bacterial virulence; Stebbins CE et al.; An important mechanism underlying the strategies used by microbial pathogens to manipulate cellular functions is that of functional mimicry of host activities . In some cases, mimicry is achieved through virulence factors that are direct homologues of host proteins . In others, convergent evolution has produced new effectors that, although having no obvious amino-acid sequence similarity to host factors, are revealed by structural studies to display mimicry at the molecular level. J Interferon Cytokine Res, 2001 Jul, 21(7), 485 - 94 IFN-gamma inhibits lipopolysaccharide-induced interleukin-1 beta in primary murine macrophages via a Stat1-dependent pathway; De Boer ML et al.; Interleukin-1 (IL-1) plays an important role in host defenses against microbial pathogens . Excessive production of this cytokine, however, may be responsible in part for the lethality observed during sepsis . Our studies show that interferon-gamma (IFN-gamma) downregulates lipopolysaccharide (LPS)-induced interleukin-1beta (IL-1beta) transcription in primary macrophages . This phenomenon does not occur in splenocytes or bone marrow-derived macrophages from signal transducer and activator of transcription (Stat1)-deficient mice, suggesting that Stat1, a transcription factor involved in IFN signaling, plays a critical role in this process . Moreover, nitric oxide (NO) was also involved in the downregulation of LPS-induced IL-1 by IFN, as addition of the inducible nitric oxide synthase (iNOS) inhibitor L-N(6)-(1-iminoethyl)lysine (NIL) negated the effect . Kinetic analysis of IL-1 and IFN levels in LPS-treated mice in vivo suggests that IFN-mediated inhibition of IL-1 might be an important negative feedback mechanism for limiting IL-1 generation in vivo. Org Lett, 2001 Aug 23, 3(17), 2677 - 80 Stereoselective synthesis of pseudopeptide microbial agent AI-77-B; Ghosh AK et al.; {structure: see text} . An efficient and highly stereoselective synthesis of the gastroprotective natural product AI-77-B is described . The stereocenters of the hydroxy amino acid moiety were generated by an ester-derived titanium-enolate-mediated syn-aldol reaction, a Curtius rearrangement, and application of Dondoni's aldehyde homologation . Condensation with the dihydroisocoumarin fragment and subsequent deprotecting transformations furnished optically active AI-77-B. CLAO J, 2001 Jul, 27(3), 125 - 36 Seven-day extended wear and 30-day continuous wear of high oxygen transmissibility soft silicone hydrogel contact lenses: a randomized 1-year study of 504 patients; Nilsson SE; PURPOSE: To compare the performance and complication rates of PureVision (Bausch & Lomb, Inc.) high Dk/t silicone hydrogel lenses in 30-day continuous wear and 7-day extended wear . METHODS: Five-hundred four (504) patients were randomized to 30-day continuous wear (353 patients) or to 7-day extended wear (151 patients) and followed for 12 months . RESULTS: Eighty percent of patients did not report any symptoms/complaints at the follow-up exams . There were no cases of microbial keratitis . The annual incidence of the four most common clinically significant positive slit lamp findings related to lens wear for the 30-day and the 7-day groups, respectively, were as follows: corneal staining, 10.5% and 10.6%; corneal infiltrates, 4.6% and 2.3%; slight epithelial edema, 2.0% and 3.6%; and tarsal conjunctival abnormalities, 1.6% and 3.0% . There was no significant difference in complication rates between the groups . For reasons related to lens wear, 7.6% in the 30-day group and 13.2% in the 7-day group were dropped from the study . The patients' subjective judgment of comfort, visual quality, freedom from dryness, and lens handling varied from 89 to 95 on a scale of 0 to 100 . The success rate was 82.9%, slightly better for the 30-day group (84.4%) than for the 7-day group (79.5%) . CONCLUSION: The complication rate was low . Sight-threatening events, such as bacterial keratitis did not occur . Inflammatory changes were seen, although at a low rate . Anterior segment changes related to hypoxia were minimal . Limbal and bulbar hyperemiadecreased significantly after switching patients to PureVision lenses . There was no significant difference in complication rates between the 30-day group and the 7-day group. Environ Technol, 2001 Jul, 22(7), 781 - 90 Comparison of two biocides--carbamate and glutaraldehyde--in the control of fouling in pulp and paper industry; Pereira MO et al.; Formation of fouling deposits is a serious problem facing paper mills . Despite the search for alternative methods, chemical biocides still represent the chief countermeasure to control microbial growth and general fouling buid-up in pulp and paper mills . The purpose of this work was to determine the effect of two biocides (carbamate and glutaraldehyde) on both planktonic cells and fouling layers of a paper machine system . A flow system was used for the study of fouling accumulation in an industrial white water circuit . Both biocides proved to be more effective in reducing the microbial loading of the white water circuit than the deposit accumulated on the stainless steel surfaces . Carbamate, in contrast to glutaraldehyde, had the ability of promoting cell agglomeration since the microbial loading decreased much more when the white water, treated with carbamate, was filtered through a filter-linen . The retention of suspended cells in the cellulose fibres acquires major importance since it is obtained by using an already existing physical process (filtration), which strongly enhances the overall microbial reduction obtained with the addition of the carbamate, without increasing the economic costs . These results also suggest that the use of conventional retention agents in pulp and paper processes can be efficient in controlling unwanted microbial effects. J Clin Immunol, 2001 Jul, 21(4), 286 - 92 Altered expression of L-selectin (CD62L) on polymorphonuclear neutrophils of children vertically infected with human immunodeficiency virus type 1; Meddows-Taylor S et al.; The expression of the leukocyte adhesion molecule L-selectin (CD62L) on polymorphonuclear neutrophils (PMN) and circulating levels of the soluble form of the receptor (sCD62L) were determined for a group of HIV-1-infected children, categorized as having mild or severe disease, and a group of uninfected control children . The fluorescence intensity of CD62L on PMN was significantly reduced in the HIV-1-infected children with mild disease compared to the uninfected controls . The proportion of lymphocytes expressing CD62L, as well as their corresponding fluorescence intensities, was significantly reduced in both the mild and the severe disease groups compared to the uninfected children, while peripheral levels of sCD62L were significantly elevated in the HIV-1-infected children with mild and severe disease compared to the controls . Altered cell migration resulting from reduced expression of CD62L may be an important contributor to the increased susceptibility to secondary microbial infections seen in HIV-1-infected children. Environ Sci Technol, 2001 Aug 1, 35(15), 3169 - 74 Chromium diffusion and reduction in soil aggregates; Tokunaga TK et al.; The distribution of metal contaminants such as chromium in soils can be strongly localized by transport limitations and redox gradients within soil aggregates . Measurements of Cr(VI) diffusion and reduction to Cr(III) were obtained in soil columns representing transects into soil aggregates in order to quantify influences of organic carbon (OC) and redox potentials on Cr transport distances and microbial community composition . Shifts in characteristic redox potentials, and the extent of Cr(VI) reduction to Cr(III) were related to OC availability . Depth profiles of Cr(VI, III) obtained with micro X-ray absorption near edge structure (micro-XANES) spectroscopy reflected interdependent effects of diffusion and spatially dependent redox potentials on reduction kinetics and microbial community composition . Shallow diffusion depths (2-10 mm) and very sharply terminated diffusion fronts in columns amended with OC (80 and 800 ppm) reflected rapid increases in Cr reduction kinetics over very short (mm) distances . These results suggest that Cr contamination in soils can be restricted to the outsides of soil aggregates due to localized transport and rapid reduction and that bulk sample characterization is inadequate for understanding the controlling biogeochemical processes. Bioorg Med Chem, 2001 Aug, 9(8), 1985 - 92 Microbial and reducing agents catalyze the rearrangement of taxanes; Sun DA et al.; 5alpha, 7beta, 9alpha, 10beta, 13alpha-Pentahydroxy-4(20),11(12)-taxadiene derivative 1 was converted to two unprecedented 1(15-->11)abeo-taxanes and a taxane derivative with a C10-C11 double bond by Absidia coerula ATCC 10738a . A similar compound was obtained from treatment with zinc of a triacetoxy-4(20),11(12)-taxadiene derivative. Cell Mol Biol (Noisy-le-grand), 2001 Jun, 47(4), 637 - 51 Role of interleukin-13 in innate and adaptive immunity; Brubaker JO et al.; Initially thought to be functionally redundant with IL-4 as a predominant anti-inflammatory factor secreted during type-2 T-cell responses, IL-13 possesses a number of additional properties that distinguish it from IL-4 in addition to having both anti-inflammatory and immune activating properties . This review centers primarily on the role of IL-13 in the regulation of cellular functions of innate immunity and acquired immunity against certain microbial pathogens . First, we discuss IL-13's regulation of innate cell targets and its impact on inflammation, antigen uptake and antigen presentation . Second, we focus on IL-13's involvement in acquired immunity to infectious helminths and protozoa . The role of this cytokine in immune responses is still being determined but evidence to date suggests this molecule has been conserved as an important regulatory factor involved in both early innate and late adaptive responses. Acta Odontol Scand, 2001 Jun, 59(3), 154 - 60 Clinical, pathological and immunological aspects of periodontal disease; Kinane DF et al.; The inflammatory and immune responses during the development and progression of periodontitis are reviewed . Susceptibility to periodontitis may be related to whether plasma cells predominate in the tissues of an individual, or a site, in response to the microbial insult from dental plaque . The tendency for an individual or site to form an extensive plasma cell infiltrate may indicate an inability to defend against periodontopathogenic bacteria and thus a predisposition to periodontitis . Selected pertinent areas of current interest in cellular and humoral immunology are considered within the periodontal context . These topical issues include (a) homing of immune and inflammatory cells to target tissues; (b) the local proliferation and synthetic activity of immune and inflammatory cells; (c) the cytokine profile of the inflammatory and immune cells; and (d) the immunoglobulin subclasses of locally produced antibodies. Acta Odontol Scand, 2001 Jun, 59(3), 145 - 53 The mucosal immune system: from specialized immune defense to inflammation and allergy; Kiyono H et al.; The mucosal immune system is a first line of defense against foreign antigens, including microbial and dietary antigens . Under normal circumstances, the mucosal immune system employs tightly regulated dynamic mucosal intra- and internets consisting of inductive and effector sites for the induction of an appropriate immunological homeostasis between the host and mucosal environments . The common mucosal immune system (CMIS), which interconnects between inductive (e.g . Peyer patch) and effector (e.g . intestinal lamina propria) tissues for the induction of the IgA response, is well characterized . Recent results provide strong evidence for the presence of a CMIS-independent IgA induction pathway . Two distinct subsets of mucosal IgA-committed B cells termed B-1 and B-2, are associated with CMIS-independence and CMIS-dependent cascades respectively . In some cases, the breakdown of this tightly regulated mucosal immune system leads to pathological responses to different gut environmental antigens . As a result, disorders such as inflammatory bowel disease (e.g . IBD) and allergic gastroenteropathy can be evoked in the gastrointestinal tissues . Recently, many studies have described possible molecular and cellular mechanisms for this dysfunction in the gastrointestinal tissues by using murine models with specific gene manipulation . In this review we summarize recent findings from our group concerning the CMIS-dependent and CMIS-independent IgA induction pathways and gastrointestinal diseases (IBD and intestinal allergic diseases) . These observations may provide useful information for the development of new mucosal immune therapy. Folia Microbiol (Praha), 2001, 46(1), 53 - 5 Application of flow cytometry for ecological monitoring of the rumen microbial ecosystem; Lipoglavsek L et al.; Flow cytometry in combination with fluorescently labeled ribosomal RNA oligonucleotide probes was used for enumeration and monitoring of ruminal bacteria . The polyanionic azo dye Trypan Blue was used for discrimination between live bacterial cells and inorganic particles and the separation was further improved by lysozyme treatment and sonication . Cy3-labeled universally conserved probe EUB338 and FITC-labeled Prevotella bryantii specific probe PBB14 were used for in situ hybridization in mixed culture experiments and in samples of crude rumen fluid . The results were analyzed by flow cytometry . The separation of P . bryantii and Butyrivibrio fibrisolvens, another ruminal bacterium, in mixed culture experiments was satisfactory and enabled monitoring of these bacteria in a test system . P . bryantii cells were detected in crude rumen fluid samples only after supplementation with pure culture cells; this implicates a low concentration of P . bryantii cells in vivo (less than 100/nL, i.e . 10(5) per mL). Plant Physiol, 2001 Aug, 126(4), 1598 - 608 A novel phytase with sequence similarity to purple acid phosphatases is expressed in cotyledons of germinating soybean seedlings; Hegeman CE et al.; Phytic acid (myo-inositol hexakisphosphate) is the major storage form of phosphorus in plant seeds . During germination, stored reserves are used as a source of nutrients by the plant seedling . Phytic acid is degraded by the activity of phytases to yield inositol and free phosphate . Due to the lack of phytases in the non-ruminant digestive tract, monogastric animals cannot utilize dietary phytic acid and it is excreted into manure . High phytic acid content in manure results in elevated phosphorus levels in soil and water and accompanying environmental concerns . The use of phytases to degrade seed phytic acid has potential for reducing the negative environmental impact of livestock production . A phytase was purified to electrophoretic homogeneity from cotyledons of germinated soybeans (Glycine max L . Merr.) . Peptide sequence data generated from the purified enzyme facilitated the cloning of the phytase sequence (GmPhy) employing a polymerase chain reaction strategy . The introduction of GmPhy into soybean tissue culture resulted in increased phytase activity in transformed cells, which confirmed the identity of the phytase gene . It is surprising that the soybean phytase was unrelated to previously characterized microbial or maize (Zea mays) phytases, which were classified as histidine acid phosphatases . The soybean phytase sequence exhibited a high degree of similarity to purple acid phosphatases, a class of metallophosphoesterases. Infect Immun, 2001 Sep, 69(9), 5270 - 7 Potent stimulation of the innate immune system by a Leishmania brasiliensis recombinant protein; Borges MM et al.; The interaction of the innate immune system with the microbial world involves primarily two sets of molecules generally known as microbial pattern recognition receptors and microbial pattern recognition molecules, respectively . Examples of the former are the Toll receptors present particularly in macrophages and dendritic cells . Conversely, the microbial pattern recognition molecules are conserved protist homopolymers, such as bacterial lipopolysaccharides, lipoteichoic acids, peptidoglycans, glucans, mannans, unmethylated bacterial DNA, and double-strand viral RNA . However, for protists that lack most of these molecules, such as protozoans, the innate immune system must have evolved receptors that recognize other groups of microbial molecules . Here we present evidence that a highly purified protein encoded by a Leishmania brasiliensis gene may be one such molecule . This recombinant leishmanial molecule, a homologue of eukaryotic ribosomal elongation and initiation factor 4a (LeIF), strongly stimulates spleen cells from severe combined immunodeficient (SCID) mice to produce interleukin-12 (IL-12), IL-18, and high levels of gamma interferon . In addition, LeIF potentiates the cytotoxic activity of the NK cells of these animals . Because LeIF is a conserved molecule and because SCID mice lack T and B lymphocytes but have a normal innate immune system (normal reticuloendothelial system and NK cells), these results suggest that proteins may also be included as microbial pattern recognition molecules . The nature of the receptor involved in this innate recognition is unknown . However, it is possible to exclude the Toll receptor Tlr4 as a putative LeIF receptor because the gene encoding this receptor is defective in C3H/HeJ mice, the mouse strain used in the present studies. J Invertebr Pathol, 2001 Jul, 78(1), 1 - 8 Adult survival, maturation, and reproduction of the desert locust Schistocerca gregaria infected with the fungus Metarhizium anisopliae var acridum; Blanford S et al.; Studies were conducted with two different doses of Metarhizium anisopliae var acridum to examine the effects on survival and reproductive potential of adult Schistocerca gregaria under conditions that either limited thermoregulation or enabled optimal thermoregulation . Adult S . gregaria infected with the fungal pathogen showed either a rapid and high mortality at relatively constant temperatures or a much reduced mortality and lengthened survival time when allowed to thermoregulate . Mortality rate varied from >90% after 10 days under constant temperature conditions to 66% after 70 days under optimal thermoregulatory conditions . Effects of infection on maturation and reproduction depended on the age of the adults at the time of inoculation, the nighttime temperature regime, the fungal dose, and the length of time of the monitoring period . No difference in reproductive behaviors in treated and control insects were found in one experiment that utilized older adults and was conducted over 25 days . In a second experiment with newly fledged locusts, differences in maturation rates and total reproductive output were observed due to infection . The results from these experiments are discussed in terms of the potential of M . anisopliae var acridum to alter the balance of insect endocrine systems and the importance of the assessment of behavioral changes and their impact on microbial control agents in the long term . Curr Opin Immunol, 2001 Aug, 13(4), 471 - 8 CD1-specific T cells in microbial immunity; Gumperz JE et al.; Recent results strengthen evidence that CD1-restricted T cells play important roles in host defense against microbial infections . Human subjects recently infected with Mycobacterium tuberculosis showed elevated responses to CD1c-mediated presentation of a microbial lipid antigen, compared with control donors . Activation of CD1d-restricted NKT cells with a synthetic glycolipid antigen results in improved immune responses to several infectious pathogens. Biochem Soc Trans, 2001 Aug, 29(Pt 4), 598 - 601 Why and how are peptide-lipid interactions utilized for self defence? Matsuzaki K. Animals defend themselves against invading pathogenic micro-organisms by utilizing cationic anti-microbial peptides, which rapidly kill various micro-organisms without exerting toxicity against the host . Physicochemical peptide-lipid interactions provide attractive mechanisms for innate immunity . Many of these peptides form amphipathic secondary structures (alpha-helices and beta-sheets) which can selectively interact with anionic bacterial membranes by electrostatic interaction . Rapid, peptide-induced membrane permeabilization is an effective mechanism of anti-microbial action . Magainin 2 from frog skin forms a dynamic peptide-lipid supramolecular-complex pore that allows mutually coupled transmembrane transport of ions and lipids . The peptide molecule is internalized upon the disintegration of the pore . Several anti-microbial peptides are known to work synergistically. Eur J Clin Pharmacol, 2001 Jun, 57(3), 211 - 9 Microdialysis . A novel tool for clinical studies of anti-infective agents; Joukhadar C et al.; In vivo microdialysis (MD) is an innovative clinical technique that has been employed in preclinical research and metabolic studies in patients for more than a decade . Recently, MD has been adopted for human drug studies and has opened up the opportunity to quantify tissue drug distribution in vivo . The particular advantage of MD for the anti-infective field relates to the fact that MD allows for online measurement of the unbound, pharmacologically active drug fraction in the interstitial space fluid (ISF), the anatomically defined target site for most bacterial infections . The aim of this review is to provide an overview of the current literature about MD in anti-microbial drug studies . It will be shown that MD has become feasible in most human tissues including brain and lung . So far, several MD studies have demonstrated that anti-microbial concentrations at the effect site may be subinhibitory, although effective concentrations are attained in serum, a finding that has significant impact on clinical decision making . In addition to its property as a pharmacokinetic sampling technique, MD offers unique opportunities in pharmacokinetic-pharmacodynamic (PK-PD) research and has the potential to streamline the decision process on proper drug dosing in drug development. Regul Pept, 2001 Sep 15, 101(1-3), 157 - 61 Human alpha-defensin 1 (HNP-1) inhibits adenoviral infection in vitro; Bastian A et al.; Adenoviral gene transfer is a promising tool for direct treatment of cystic fibrosis by local application of the CFTR-gene via the airway . However, various host defense mechanisms reduce the adenoviral infectivity and hereby the success of adenoviral transduction . Twenty-eight of 62 BALs from various patients exerted strong inhibition of adenoviral infection of 293 cells . This soluble activity could be attributed to larger peptides rather than to small molecules . Beside immunoglobulins, certain epithelial cell-derived anti-microbial polypeptides called defensins might be involved . Therefore, we investigated the inhibitory potential of the defensins HNP-1 and HBD-2 on adenoviral infectivity . 293 cells infected with adenovirus-type 5 were treated with both peptides . Compared to control, HNP-1 reduced adenoviral infection by more than 95% if administered at 50 microg/ml, and the IC50-value was 15 microg/ml . In contrast, HBD-2 was much less efficient and did not block adenoviral infection at doses up to 50 microg/ml . Our data demonstrate that the presence of certain polypeptides in the BAL, i.e . the defensin HNP-1, might be the major obstacle for adenoviral gene transfer, particularly in patients with inflammatory diseases. Am J Ind Med, 2001 Aug, 40(2), 199 - 210 Medical aspects of global warming; Yoganathan D et al.; BACKGROUND: Global warming is caused by increased carbon dioxide (CO2)resulting in a greenhouse effect with enhanced warming of the earth . Measurements of CO2 show a steady increase over the past 30 years caused by the burning of fossil fuels and from the loss of natural CO2 sinks . A 100-year increase in global temperature by 0.3 to 0.6 degrees C is reflected in atmospheric warming, glacier shrinkage, and rising sea levels . OBJECTIVES: Planetary ecosystem dynamics are being altered, challenging public health . It is predicted that morbidity and mortality will increase as a result of heat stress, as seen in recent heat waves in the U.S . Weather disaster effects will increase in number and magnitude, and both noninfectious and infectious diseases may flourish . A significant challenge will be the changes in life cycles of microbial species due to the warmer environs . Specific increases in incidence have been noted for vector-borne diseases, in addition to pulmonary findings, cardiovascular morbidity, neurological diseases, and occupational diseases . CONCLUSIONS: Warming can be demonstrated by the observed changes that have already occurred in the environment, particularly the thinning of polar ice caps . The United States Global Research Program has been established to coordinate research activities, which responds to issues deemed important by the United Nations Framework Convention on Climate Change . Research issues pertain to the scientific uncertainties in the greenhouse effect, temperature measurements at various atmospheric levels and latitudes, and impact on biota redistribution . The Kyoto Protocol has mandated specific solutions, e.g., a 7% reduction in CO2 levels within 10 years . Future recommendations involve supporting new technologies that are available to decrease emissions as well as understanding the role that occupational and environmental specialists have in global warming recognition . Proc Natl Acad Sci U S A, 2001 Aug 14, 98(17), 9853 - 8 Epub 2001 Aug 07. DNA/DNA hybridization to microarrays reveals gene-specific differences between closely related microbial genomes; Murray AE et al.; DNA microarrays constructed with full length ORFs from Shewanella oneidensis, MR-1, were hybridized with genomic DNA from nine other Shewanella species and Escherichia coli K-12 . This approach enabled visualization of relationships between organisms by comparing individual ORF hybridizations to 164 genes and is further amenable to high-density high-throughput analyses of complete microbial genomes . Conserved genes (arcA and ATP synthase) were identified among all species investigated . The mtr operon, which is involved in iron reduction, was poorly conserved among other known metal-reducing Shewanella species . Results were most informative for closely related organisms with small subunit rRNA sequence similarities greater than 93% and gyrB sequence similarities greater than 80% . At this level of relatedness, the similarity between hybridization profiles was strongly correlated with sequence divergence in the gyrB gene . Results revealed that two strains of S . oneidensis (MR-1 and DLM7) were nearly identical, with only 3% of the ORFs hybridizing poorly, in contrast to hybridizations with Shewanella putrefaciens, formerly considered to be the same species as MR-1, in which 63% of the ORFs hybridized poorly (log ratios below -0.75) . Genomic hybridizations showed that genes in operons had consistent levels of hybridization across an operon in comparison to a randomly sampled data set, suggesting that similar applications will be informative for identification of horizontally acquired genes . The full value of microbial genomic hybridizations lies in providing the ability to understand and display specific differences between closely related organisms providing a window into understanding microheterogeneity, bacterial speciation, and taxonomic relationships. J Med Primatol, 2001 Apr, 30(2), 127 - 30 Subcutaneous hemangiosarcomas in a rhesus macaque (Macaca mulatta); Myers DD Jr et al.; Hemangiosarcoma is a malignant tumor of vascular endothelial cell origin . The occurrence of hemangiosarcoma in nonhuman primates has been rarely documented . An adult male rhesus monkey was reported having a firm subcutaneous swelling, approximately 4.5 cm in diameter, on the ventral midline of the abdomen . Fine-needle aspiration, microbial culture, biopsy, radiographs, exploratory laparotomy, histopathology, immunohistochemistry, hematology, and serology were performed . A second subcutaneous mass approximately 4.5 x 4.0 x 2.7 cm developed on the ventral midline several weeks later . A fine-needle aspirate of the first mass consisted of numerous erythrocytes with few polymorphonuclear cells and lymphocytes . Histopathology showed foci of spindle-shaped cells surrounding the vascular spaces . Many spindle-shaped cells had prominent nucleoli, and mitotic figures could occasionally be seen . Immunohistochemical staining of the masses for Factor VIII-related antigen, an endothelial cell and tumor marker, yielded positive results . Both masses were consistent with hemangiosarcoma. J Immunol, 2001 Aug 15, 167(4), 2411 - 7 Down-regulation of IgE and IgG4 antibodies to tetanus toxoid and diphtheria toxoid by covaccination with cellular Bordetella pertussis vaccine; Gruber C et al.; Pertussis (P) toxin acts as adjuvant for IgE formation against simultaneously administered Ags in animal models . P vaccination may also have an adjuvant impact on IgE formation against coadministered diphtheria (D) and tetanus (T) Ags in humans . Sera of 103 D-T-P-immunized and 319 D-T-immunized children aged 2 years were analyzed for IgE, IgG4, and IgG to D and T (radioallergosorbent test), total IgE and IgE against common inhalant allergens (CAP radioallergosorbent test fluoroenzyme immunoassay) . Fewer D-T-P- than D-T-immunized children had sera positive for T-IgE (12.6 vs 53.6%, p < 0.001), T-IgG4 (71.6 vs 89.2%, p < 0.001), D-IgE (31.0 vs 70.5%, p < 0.001), and D-IgG4 (85.2 vs 93.4%, p = 0.039) . Suppression of T-IgE was not dependent on the cutoff chosen for a positive test result, but was dependent on the proportion of D-T immunizations given with P . The risk for sensitization to common environmental allergens did not differ (odds ratio 0.953, 95% confidence interval 0.815-1.114) . No significant differences between D-T- and D-T-P-immunized children were found with regard to T-IgG or D-IgG . In summary, IgE and IgG4 (but not IgG) serum levels to coadministered D- and T-Ags are suppressed among P-immunized children as compared with nonimmunized children . These results suggest that the presence of a microbial product during Ag exposure can down-regulate an IgE/IgG4 response in humans. J Immunol, 2001 Aug 15, 167(4), 2193 - 201 Toxoplasma gondii tachyzoites inhibit proinflammatory cytokine induction in infected macrophages by preventing nuclear translocation of the transcription factor NF-kappa B; Butcher BA et al.; Control of microbial infection requires regulated induction of NF-kappaB-dependent proinflammatory cytokines such as IL-12 and TNF-alpha . Activation of this important transcription factor is driven by phosphorylation-dependent degradation of the inhibitory IkappaB molecule, an event which enables NF-kappaB translocation from the cytoplasm to the nucleus . In this study, we show that intracellular infection of macrophages with the protozoan parasite Toxoplasma gondii induces rapid IkappaB phosphorylation and degradation . Nevertheless, NF-kappaB failed to translocate to the nucleus, enabling the parasite to invade cells without triggering proinflammatory cytokine induction . Infected cells subsequently subjected to LPS triggering were severely crippled in IL-12 and TNF-alpha production, a result of tachyzoite-induced blockade of NF-kappaB nuclear translocation . Our results are the first to demonstrate the ability of an intracellular protozoan to actively interfere with the NF-kappaB activation pathway in macrophages, an activity that may enable parasite survival within the host. J Clin Invest, 2001 Aug, 108(3), 485 - 93 Plasma CD14 decreases monocyte responses to LPS by transferring cell-bound LPS to plasma lipoproteins; Kitchens RL et al.; CD14, a myeloid cell-surface receptor and soluble plasma protein, binds LPS and other microbial molecules and initiates the innate immune response to bacterial invasion . The blood concentration of soluble CD14 (sCD14) increases during the systemic response to infection . Although high sCD14 blood levels have correlated with increased risk of dying from severe sepsis, sCD14 can diminish cell responses to LPS . We show here that in human serum, sCD14 increases the rate at which cell-bound LPS is released from the monocyte surface and binds to plasma lipoproteins . This enhanced rate of LPS efflux is associated with a significant reduction in the ability of monocytes to produce cytokines in response to LPS . Serum from septic patients reduced the LPS-monocyte interaction by as much as tenfold, and depletion of sCD14 from the serum restored LPS-monocyte binding and release kinetics to near normal levels . In serum from septic patients, monocyte-bound LPS also moved more rapidly into lipoproteins, which completely neutralized the biologic activity of the LPS that bound to them . In human plasma, sCD14 thus diminishes monocyte responses to LPS by transferring cell-bound LPS to lipoproteins . Stress-related increases in plasma sCD14 levels may help prevent inflammatory responses within the blood. Anal Biochem, 2001 Aug 15, 295(2), 129 - 37 Quantification of intracellular metabolites in Escherichia coli K12 using liquid chromatographic-electrospray ionization tandem mass spectrometric techniques; Buchholz A et al.; The quantitative comprehension of microbial metabolic networks is a prerequisite for an efficient rational strain improvement ("metabolic engineering") . It is therefore necessary to accurately determine the concentration of a large number of reactants (i.e., metabolites, nucleotides, cofactors) in order to understand "in vivo" reaction kinetics . Quantification of intracellular concentrations of glycolytic intermediates and nucleotides in Escherichia coli K12 using a perchloric acid extraction and an LC-ESI-MS method was achieved . Intracellular metabolites (e.g., glucose 6-phosphate, fructose 1,6-bisphosphate, 6-phospho gluconate, acetyl-CoA, adenine nucleotides) were quantified under defined (glucose-limited steady-state) growth conditions . The method was verified by comparing the intracellular metabolite concentrations measured via LC-ESI-MS with enzymatic determinations . It is thus possible to identify and quantify more than 15 intracellular metabolites in parallel with a minimal amount of sample volume . Arch Biochem Biophys, 2001 Aug 15, 392(2), 279 - 86 Characterization of a novel laccase produced by the wood-rotting fungus Phellinus ribis; Min KL et al.; The white-rot fungus Phellinus ribis produced a single form of laccase, which was purified to apparent electrophoretic homogeneity from cultures induced with 2,5-xylidine . This protein was a dimer, consisting of two subunits of 76 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis . Carbohydrate analysis revealed that the enzyme contained about 28% carbohydrate content . The laccase appeared to be different from other known laccases by the UV-visible absorption spectrum analysis . One enzyme molecule contained one copper, one manganese, and two zinc atoms . The laccase showed optimal activity at pH 4.0-6.0, 5.0, and 6.0 with 2,6-dimethoxyphenol, ABTS {2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)}, and syringaldazine, respectively . The enzyme preferably oxidized dimethoxyphenol and aromatic amine compounds . The stability of the laccase was low at acidic pH, whereas it showed high stability at neutral pH and mild temperature . The N-terminal amino acid sequence revealed a very low homology with other microbial laccases . With some substrates, the addition of manganese and H2O2 resulted in a remarkable increase in the oxidation rate . Without an appropriate phenolic substrate, the enzyme could not oxidize Mn(II) in the presence of H2O2 or pyrophosphate . Front Biosci, 2001 Aug 01, 6, D944 - 53 The structure and functions of human lysophosphatidic acid acyltransferases; Leung DW; Lysophosphatidic acid (LPA) and phosphatidic acid (PA) are two phospholipids involved in signal transduction and in lipid biosynthesis in cells . LPA acyltransferase (LPAAT), also known as 1-acyl sn-glycerol-3-phosphate acyltransferase (1-AGPAT) (EC 2.3.1.51), catalyzes the conversion of LPA to PA . Two human isoforms of LPAAT, designated as LPAAT-alpha (AGPAT1) and LPAAT-beta (AGPAT2), have been extensively characterized . These two proteins contain extensive sequence similarities to microbial, plant and animal LPAAT sequences . LPAAT-alpha mRNA is uniformly expressed throughout most tissues with the highest level found in skeletal muscle; whereas LPAAT-beta is differentially expressed, with the highest level found in heart and liver, and negligible level in brain and placenta . The LPAAT-alpha gene is located on chromosome 6p21.3, an area within the class III region of the major hiscompatibility complex (MHC) and the LPAAT-beta gene is mapped to chromosome 9q34.3 . Enhanced transcription of LPAAT-beta is suggested for neoplasm of the female genital tract . Additionally, ectopic LPAAT expression in certain cytokine-responsive cell lines can effect amplification of cellular signaling processes, such as those leading to enhancement of synthesis of tumor necrosis factor-alpha and interleukin-6 from cells following stimulation with interleukin-1beta; this suggests that the LPAAT genes represent candidates for affecting the development of certain cancers or inflammation-associated diseases. Biodegradation, 2000, 11(5), 323 - 9 Degradation of microbial polyester poly(3-hydroxybutyrate) in environmental samples and in culture; Manna A et al.; Poly(3-hydroxybutyrate) {P(3HB)} test-pieces prepared from the polymer produced by Azotobacter chroococcum were degraded in natural environments like soil, water, compost and sewage sludge incubated under laboratory conditions . Degradation in terms of % weight loss of the polymer was maximum (45%) in sewage sludge after 200 days of incubation at 30 degrees C . The P(3HB)-degrading bacterial cultures (36) isolated from degraded test-pieces showed different degrees of degradation in polymer overlayer method . The extent of P(3HB) degradation increases up to 12 days of incubation and was maximum at 30 degrees C for majority of the cultures . For most efficient cultures the optimum concentration of P(3HB) for degradation was 0.3% (w/v) . Supplementation of soluble carbon sources like glucose, fructose and arabinose reduced the degradation while it was almost unaffected with lactose . Though the cultures degraded P(3HB) significantly, they were comparatively less efficient in utilizing copolymer of 3-hydroxybutyrate and 3-hydroxyvalerate {P(3HB-co-3HV)}. Biodegradation, 2000, 11(5), 313 - 21 Quinones as terminal electron acceptors for anaerobic microbial oxidation of phenolic compounds; Cervantes FJ et al.; The capacity of anaerobic granular sludge for oxidizing phenol and p-cresol under anaerobic conditions was studied . Phenol and p-cresol were completely converted to methane when bicarbonate was the only terminal electron acceptor available . When the humic model compound, anthraquinone-2,6-disulfonate, was included as an alternative electron acceptor in the cultures, the oxidation of the phenolic compounds was coupled to the reduction of the model humic compound to its corresponding hydroquinone, anthrahydroquinone-2,6-disulfonate . These results demonstrate for the first time that the anaerobic degradation of phenolic compounds can be coupled to the reduction of quinones as terminal electron acceptor. Pediatr Pathol Mol Med, 2001 Jul-Aug, 20(4), 293 - 318 Functional mapping of surfactant protein A; McCormack FX; Surfactant protein A (SP-A) is a highly ordered, oligomeric glycoprotein that is secreted into the airspaces of the lung by alveolar type II cells and Clara cells of the pulmonary epithelium . Although research has shown that SP-A is both a calcium-dependent phospholipid-binding protein that affects surfactant structure and function and a lectin that opsonizes diverse microbial species, our understanding of the physiologically relevant roles of SP-A in the lung remains incomplete . My review focuses on the putative biological functions of SP-A that are supported by experiments in mammals and on the structural basis of SP-A function. Circ Res, 2001 Aug 3, 89(3), 244 - 50 Chlamydia pneumoniae and chlamydial heat shock protein 60 stimulate proliferation of human vascular smooth muscle cells via toll-like receptor 4 and p44/p42 mitogen-activated protein kinase activation; Sasu S et al.; An early component of atherogenesis is abnormal vascular smooth muscle cell (VSMC) proliferation . The presence of Chlamydia pneumoniae in many atherosclerotic lesions raises the possibility that this organism plays a causal role in atherogenesis . In this study, C pneumoniae elementary bodies (EBs) rapidly activated p44/p42 mitogen-activated protein kinases (MAPKs) and stimulated proliferation of VSMCs in vitro . Exposure of VSMCs derived from human saphenous vein to C pneumoniae EBs (3x10(7) inclusion forming units/mL) enhanced bromodeoxyuridine (BrdU) incorporation 12+/-3-fold . UV- and heat-inactivated C pneumoniae EBs also stimulated VSMC proliferation, indicating a role of direct stimulation by chlamydial antigens . However, the mitogenic activity of C pneumoniae was heat-labile, thus excluding a role of lipopolysaccharide . Chlamydial hsp60 (25 microg/mL) replicated the effect of C pneumoniae, stimulating BrdU incorporation 7+/-3-fold . Exposure to C pneumoniae or chlamydial hsp60 rapidly activated p44/p42 MAPK, within 5 to 10 minutes of exposure . In addition, PD98059 and U0126, which are two distinct inhibitors of upstream MAPK kinase 1/2 (MEK1/2), abolished the mitogenic effect of C pneumoniae and chlamydial hsp60 . Toll-like receptors (TLRs) act as sensors for microbial antigens and can signal via the p44/p42 MAPK pathway . Human VSMCs were shown to express TLR4 mRNA and protein, and a TLR4 antagonist abolished chlamydial hsp60-induced VSMC proliferation and attenuated C pneumoniae-induced MAPK activation and VSMC proliferation . Together these results indicate that C pneumoniae and chlamydial hsp60 are potent inducers of human VSMC proliferation and that these effects are mediated, at least in part, by rapid TLR4-mediated activation of p44/p42 MAPK. Am J Pathol, 2001 Aug, 159(2), 537 - 46 cis Interaction of the cell adhesion molecule CEACAM1 with integrin beta(3); Brummer J et al.; CEACAM1 is a cell adhesion molecule that has been implicated in a number of physiological processes (eg, tumor suppressor in epithelial tissues, potent angiogenic factor in microvessel formation, microbial receptor in human granulocytes and epithelial cells) . The mechanism of CEACAM1 action is still largely unresolved but recent findings demonstrated that the cytoplasmic CEACAM1 domain is linked indirectly to the actin-based cytoskeleton . We have isolated integrin beta(3) as an associated protein using CEACAM1 tail affinity purification . This association depends on phosphorylation of Tyr-488 in the CEACAM1 cytoplasmic domain . Confocal laser scanning microscopy confirmed in vivo colocalization of both molecules in human granulocytes and epithelial cells . Furthermore, the concentrated colocalization at the tumor-stroma interface of invading melanoma masses suggests a functional role of CEACAM1-integrin beta(3) interaction in melanoma invasion . Moreover, colocalization of the two adhesion molecules is also found at the apical surface of glandular cells of pregnancy endometrium . Colocalization of CEACAM1 and integrin beta(3) at the transitional zone from proliferative to invasive extravillous trophoblast of the maternal-fetal interface supports a role for CEACAM1/integrin beta(3) complexes in cell invasion. Trends Genet, 2001 Aug, 17(8), 429 - 31 Intrinsic errors in genome annotation; Devos D et al.; Genome sequencing is usually followed by routine annotation of protein function based on the assumption that similar sequences will have similar functions . Here, we introduce a simple calculation to estimate the magnitude of any possible annotation errors . We counted the number of discrepancies in the annotation of well-established sets of similar proteins and extrapolated these values to the pairs of similar sequences used for the annotation of different microbial genomes . We conclude that the number of potential errors in the prediction of detailed functions is higher than is usually believed. Immunity, 2001 Jul, 15(1), 127 - 35 MASP-3 and its association with distinct complexes of the mannan-binding lectin complement activation pathway; Dahl MR et al.; The mannan-binding lectin (MBL) pathway of complement activation is part of the innate immune defense . The binding of MBL to microbial carbohydrates activates the MBL-associated serine proteases (MASPs), which recruit the complement factors, C4 and C2, to generate the C3 convertase or directly activate C3 . We present a phylogenetically highly conserved member of the MBL complex, MASP-3, which is generated through alternative splicing of the MASP-1/3 gene . The designation of MASP-3 as a protease is based on homology to known MASPs . Different MBL oligomers were found to have distinct MASP composition and biological activities . MASP-1, MAp19, and direct C3-cleaving activity are associated with smaller oligomers whereas MASP-3 is found together with MASP-2 on larger oligomers . MASP-3 downregulate the C4 and C2 cleaving activity of MASP-2. Biochem Biophys Res Commun, 2001 Aug 10, 286(1), 87 - 93 Regulation of protein kinase CKII by direct interaction with the C-terminal region of p47(phox); Kim YS et al.; Protein kinase CKII is a Ser/Thr kinase which is involved in many proliferation-related processes in the cell . p47(phox) is a component of the leukocyte NADPH oxidase, which is an important element of host defense against microbial infection . In this study, we demonstrate that a truncated form of the p47(phox) lacking its N-terminal region (p47(phox)/SH3-C), but not a truncated form of the p47(phox) lacking its C-terminal region (p47(phox)/N-SH3), undergoes better phosphorylation by CKII in the presence of arachidonic acid . The yeast two-hybrid test and the glutathione S-transferase (GST) pull-down assay showed that p47(phox) interacts specifically with the regulatory beta subunit (CKIIbeta), but not with the catalytic alpha subunit (CKIIalpha) of the tetrameric CKII holoenzyme . The binding of p47(phox) to CKIIbeta requires the C-terminal region of p47(phox) and is completely abolished by addition of spermine, indicating that a highly basic region in the C-terminal region of p47(phox) contributes to binding to CKIIbeta . In addition, p47(phox) stimulates the catalytic activity of CKII holoenzyme; this stimulation also requires the C-terminal region of p47(phox) . Coimmunoprecipitation experiments showed that CKII holoenzyme interacts with p47(phox) in human neutrophils . Taken together, the present data indicate that the C-terminal region of p47(phox) plays a significant role in the arachidonic acid-dependent phosphorylation of p47(phox) by CKII and that the same region of p47(phox) associates directly with CKIIbeta and can modulate the catalytic activity of CKII holoenzyme . Nat Rev Mol Cell Biol, 2001 Aug, 2(8), 578 - 88 Pathogenic trickery: deception of host cell processes; Knodler LA et al.; Microbial pathogens cause a spectrum of diseases in humans . Although the disease mechanisms vary considerably, most pathogens have developed virulence factors that interact with host molecules, often usurping normal cellular processes, including cytoskeletal dynamics and vesicle targeting . These virulence factors often mimic host molecules, and mediate events as diverse as bacterial invasion, antiphagocytosis, and intracellular parastism. Biologicals, 2001 Mar, 29(1), 39 - 43 Development of control serum for microbial antibody tests; Uemura Y et al.; Control sera are an essential component of in-vitro clinical diagnostic reagents . We have developed a control serum for HBsAg, anti-HCV, anti-HIV and anti- Treponema pallidum testing . Since this control serum is prepared from human plasma, we paid special attention to viral safety . We incorporated three viral inactivation methods into the manufacturing process that maintain the necessary characteristics of a stable control serum . Chemosphere, 2001 Aug, 44(4), 697 - 700 Oxidation of triphenylarsine to triphenylarsineoxide by Trichoderma harzianum and other fungi; Hofmann K et al.; Arsenic resistant strains of bacteria and fungi were isolated from soil contaminated by chemical warfare agents . Until now, no metabolic products of microbial attack against the phenyl residues of the model substrate triphenylarsine (TP) were found if it was incubated together with these strains in liquid culture assays . However, one of the isolated fungi, Trichoderma harzianum As 11, was found to oxidize TP to triphenylarsineoxide (TPO) . The yeast Trichosporon mucoides SBUG 801 and the white-rot fungus Phanerochaete chrysosporium were also able to oxidize the As(III) in TP . In addition, P . chrysosporium transformed phenylarsineoxide (PAO) to phenylarsonic acid (PAA) under O2-atmosphere . By means of a respirometer system, the oxidation of TP by T . harzianum As 11 was confirmed by a significantly higher consumption of oxygen in the presence of these compounds . HPLC analysis of the oxidation products TPO and PAA in the medium of the assays provided evidence for the transfer reaction of As(III) to As(V) in organic bonds . The oxidation products TPO and PAA are more hydrophilic than TP and PAO . Therefore, it was concluded that particular fungi contribute to the mobilization of arsenic in soil contaminated by chemical warfare agents. Chemosphere, 2001 Aug, 44(4), 621 - 5 Effect of photosensitizer riboflavin on the fate of 2,4,6-trinitrotoluene in a freshwater environment; Cui H et al.; The effect of riboflavin (1 microM) on the fate of TNT (20 mg/l) in a natural water environment was studied . The relative contribution of photolysis, microbial assemblages and freshwater matrix to TNT degradation was examined . The rates, extent and products of TNT and riboflavin transformation were compared under different experimental conditions . It was found that riboflavin significantly enhanced the degradation of TNT in natural water environment . Thus it is a potentially useful photosensitizing agent for the treatment of TNT-contaminated surface water . Furthermore, in the presence of riboflavin, two new intermediates with max . absorption wavelength of 230 nm were found, demonstrating that transformation of TNT in the presence of riboflavin undergoes different pathways. J Vet Diagn Invest, 2001 May, 13(3), 219 - 29 Differential detection of Bartonella species and strains in cat scratch disease diagnostics by polymerase chain reaction amplification of 16S ribosomal RNA gene; Tapp RA et al.; Cat scratch disease (CSD) has been difficult to diagnose in animals because of the protracted clinical course of infection and the quiescent phases when the microbial culprit lies dormant . The causative agent in CSD appears to be multiple species and strains of Bartonella . Using polymerase chain reaction (PCR) techniques for amplification of highly variable regions of the 16S ribosomal RNA (rRNA) gene sequence, a very sensitive species- and strain-specific assay for CSD-causing Bartonella species was developed . PCR primers were designed to specifically amplify the 16S rRNA gene of Bartonella species but not of other microbial pathogens . This initial PCR was multiplexed with a universal primer set, based on conserved sequence regions in the 16S rRNA gene, that provides a 162-bp fragment in all species tested . Subsequently, 3 distinct nested PCR primer sets enabled the individual amplification and specific detection of Bartonella henselae type 1, B . henselae type II, and B . clarridgeae . Thus, this 2-step PCR procedure enabled the sensitive detection and identification of these species and the B . henselae genotype by exploiting minor sequences differences . Verification of these results were demonstrated with both sequencing and ligase chain reaction techniques . The diagnostic usefulness of this CSD test has been demonstrated by the analysis of specimens from control and infected cats . The diagnosis was confirmed and the specific B . henselae strain was correctly identified in peripheral blood specimens obtained from control and strain-specific CSD-infected cats . Such an accurate and sensitive diagnostic tool for the detection and identification of CSD causative agents should be a useful for the medical, veterinary, and scientific communities. Bioresour Technol, 2001 Sep, 79(2), 147 - 54 Influence of one or two successive annual applications of organic fertilisers on the enzyme activity of a soil under barley cultivation; Marcote I et al.; The effect of cow manure and two rates of addition of municipal solid waste (MSW) compost on the enzymatic activity of a soil supporting barley cultivation was studied and compared with mineral fertilisation (MF) . The experiment was carried out in unirrigated land in field conditions for two years . One set of plots was fertilised only once, at the start of the experiment, while another set of plots was fertilised annually (before each sowing) . In general, the organic amendments stimulated soil enzyme activity but mineral fertilisation did not . The annual addition of large quantities of MSW compost, in general, led to lower levels of enzyme activity than similar rates of amendment in the plots receiving a single addition, probably because of the toxic effect which the heavy metals incorporated with the MSW compost had on microbial development . In the second year, plot receiving a single application of organic amendment showed higher protease hydrolysing casein, beta-glucosidase and dehydrogenase activities than control or soil with mineral fertilisation . This implied that the addition of organic waste, and particularly MSW compost, had a catalysing effect in the soil which lasted for the following years . Barley yields obtained with organic amendments were, in general, similar to, or even higher, than those obtained with mineral fertilisation . The annual addition of high doses of compost had an inhibitory effect on enzyme activity and barley yield (compared with the results obtained with the low addition of compost) due to the negative effect of the heavy metals incorporated with the compost. Environ Sci Technol, 2001 Jul 15, 35(14), 2961 - 6 Evidence for simultaneous abiotic-biotic oxidations in a microbial-Fenton's system; Howsawkeng J et al.; The conditions that support the simultaneous activity of hydroxyl radicals (OH.) and heterotrophic aerobic bacterial metabolism were investigated using two probe compounds: (1) tetrachloroethene (PCE) for the detection of OH . generated by an iron-nitrilotriacetic acid (Fe-NTA) catalyzed Fenton-like reaction and (2) oxalate (OA) for the detection of heterotrophic metabolism of Xanthobacter flavus . In the absence of the bacterium in the quasi-steady-state Fenton's system, only PCE oxidation was observed; conversely, only OA assimilation was found in non-Fenton's systems containing X . flavus . In combined Fenton's-microbial systems, loss of both probes was observed . PCE oxidation increased and heterotrophic assimilation of OA declined as a function of an increase in the quasi-steady-state H2O2 concentration . Central composite rotatable experimental designs were used to determine the conditions that provide maximum simultaneous abiotic-biotic oxidations, which were achieved with a biomass level of 10(9) CFU/mL, 4.5 mM H2O2, and 2.5 mM Fe-NTA . These results demonstrate that heterotrophic bacterial metabolism can occur in the presence of hydroxyl radicals . Such simultaneous abiotic-biotic oxidations may exist when H2O2 is injected into the subsurface as a microbial oxygen source or as a source of chemical oxidants . In addition, hybrid abiotic-biotic systems could be used for the treatment of waters containing biorefractory organic contaminants present in recycle water, cooling water, or industrial waste streams. J Biol Chem, 2001 Oct 5, 276(40), 37692 - 9 Epub 2001 Jul 26. Toll-like receptor 2 (TLR2) and TLR4 differentially activate human dendritic cells; Re F et al.; Toll-like receptors (TLRs) mediate cell activation by various microbial products . Here, we demonstrate that activation of dendritic cells by TLR2 or TLR4 agonists, although it led to comparable activation of NF-kappa B and mitogen-activated protein kinase (MAPK) family members, resulted in striking differences in cytokine and chemokine gene transcription, suggesting that TLR2 and TLR4 signaling is not equivalent . A TLR4 agonist specifically promoted the production of the Th1-inducing cytokine interleukin (IL) 12 p70 and the chemokine interferon-gamma inducible protein (IP)-10, which is also associated to Th1 responses . In contrast, TLR2 stimulation failed to induce IL-12 p70 and interferon-gamma inducible protein (IP)-10 but resulted in the release of the IL-12 inhibitory p40 homodimer, producing conditions that are predicted to favor Th2 development . TLR2 stimulation also resulted in preferential induction of IL-8 and p19/IL-23 . Involvement of phosphatidylinositol 3-kinase and p38 MAPK in the TLR-mediated induction of several cytokine and chemokine messages was demonstrated using specific inhibitors . Thus, TLRs can translate the information regarding the nature of pathogens into differences in the cytokines and chemokines produced by dendritic cells and therefore may contribute to the polarization of the acquired immune response. Q J Nucl Med, 2001 Jun, 45(2), 167 - 73 New concepts in infection/inflammation imaging; Rennen HJ et al.; Although autologous leukocytes, labelled with 111In or 99mTc, is still considered the "gold standard" nuclear medicine technique to image infection and inflammation, there is a great need for a less cumbersome and less hazardous approach . Over the last few decades the range of radiopharmaceuticals to investigate infectious and non-microbial inflammatory disorders is vastly expanding . Radiolabelled monoclonal antibodies and antibody-fragments, radiolabelled chemotactic peptides and cytokines, and radiolabelled antibiotics are promising new approaches in the field of nuclear medicine . Recently, positron emission tomography (PET) with 18FJDG has been introduced and has been shown to delineate infectious and inflammatory foci with high sensitivity . Here, a survey is presented of the different approaches in use or under investigation. J Appl Microbiol, 2001 Aug, 91(2), 351 - 63 Advances in disinfection testing and modelling; Lambert RJ; AIMS: To develop a set of kinetic equations which more ably describe the disinfection process . METHODS AND RESULTS: A group of functions, the fat equations, based on the model used for the quantification of microbial inhibition, was produced . These functions introduce a limit to the numbers of micro-organisms capable of being disinfected . These new expressions were shown to be more general forms of currently-used (e.g . log-linear) disinfection models, and accommodate the lags and/or tails of non-linear log-survivor--time plots . An advance in the experimental procedures used to obtain disinfection data, using an optical density technique, was developed concomitantly . CONCLUSION: The methods of analyses (experimental and modelling) allow the researcher to examine, more ably, five-minute disinfection (or specific time disinfection tests) as well as the more important disinfection rate analyses . SIGNIFICANCE AND IMPACT OF THE STUDY: The fat equations are an improvement over commonly-used rate models of disinfection, which are shown to be special cases of these equations . This raises the question as to whether our current understanding of the kinetic basis of disinfection requires revision. J Nat Prod, 2001 Jul, 64(7), 874 - 82 The complestatins as HIV-1 integrase inhibitors . Efficient isolation, structure elucidation, and inhibitory activities of isocomplestatin, chloropeptin I, new complestatins, A and B, and acid-hydrolysis products of chloropeptin I; Singh SB et al.; From the screening of a microbial extract library, isocomplestatin (1), a new axial-chiral isomer of complestatin (2) which is a known rigid bicyclic hexapeptide, was identified as a potent natural product inhibitor of HIV-1 integrase, a unique enzyme responsible for viral replication . Isocomplestatin showed inhibitory activities (IC(50)) in coupled 3'-end processing/strand transfer (200 nM), strand transfer (4 microM), and HIV-1 replication (200 nM) in virus-infected cells . Attempted large-scale isolation of 1 by the literature method, used for the isolation of complestatin, led to lower yield and limited availability . We have developed several new, two-step, high-yielding absorption/elution methods of isolation based on reverse-phase chromatography at pH 8 that are applicable to scales from one gram to potential industrial quantities . We have also discovered and determined the structure of two new congeners of 1, namely, complestatins A (4) and B (5), with almost equal HIV-1 integrase activity . They differ from 1 at C2' and C3' of the tryptophan moiety (residue F) . Selective acid hydrolysis of chloropeptin I (3), itself a known acid-catalyzed rearranged isomer of 1 and 2 (8'- vs 7'-substitution in tryptophan residue F, respectively), an isomer of complestatin, and isocomplestatin resulted in a number of fragments (6-10) with