J Mol Med, 2004 Mar, 82(3), 197 - 205 Epub 2003 Dec 13. Dichotomy between Lactobacillus rhamnosus and Klebsiella pneumoniae on dendritic cell phenotype and function; Braat H et al.; The reaction of the intestinal immune system to intestinal bacteria shows striking differences between various bacterial strains . Whereas Klebsiella pneumoniae induces a fierce proinflammatory reaction, the probiotic strain Lactobacillus rhamnosus has clear anti-inflammatory effect in gastrointestinal disease and allergy . The molecular basis for this dichotomy is poorly understood but is likely to involve different modulation of antigen-presenting dendritic cells (DC) by L . rhamnosus and K . pneumoniae . Hence we evaluated phenotypic and functional characteristics of DC matured in the presence of L . rhamnosus and K . pneumoniae . Monocyte-derived immature DC were cultured in the presence of live bacteria to obtain mature DC . Both micro-organisms induced maturation of immature DC as shown by CD83 and CD86 expression, but receptors involved in activation of Th1 cells were expressed predominantly on DC exposed to K . pneumoniae . In contrast to K . pneumoniae, maturation with L . rhamnosus resulted in lower TNF-alpha, IL-6, and IL-8 production by immature DC and lower IL-12 and IL-18 production by mature DC . Moreover, L . rhamnosus led to the development of T cells without a typical Th phenotype whereas K . pneumoniae induced a Th1 immune response, dependent mainly on IL-12 production . Thus our results strongly support the concept that differential modulation of DC explains the differences in the immune response to various bacterial strains and indicates that K . pneumoniae induces Th1 immune responses via DC. Gynakol Geburtshilfliche Rundsch, 2004 Jan, 44(1), 2 - 9 {Efficient prevention of prematurity - the Thuringian model}; Hoyme UB et al.; In two prospective projects, the effectiveness of the self-care programme for prematurity prevention developed by Saling was prevented . Pregnant women in Erfurt were shown how to perform self-measurements of their vaginal pH by means of test gloves twice a week in order to screen for any disturbances in the vaginal millieu . The women were instructed to see their physician immediately, if abnormal values (ph > or = 4.7) or other risk factors were present, in order to start Lactobacillus acidophilus therapy or, in cases of bacterial vaginosis, treatment with intravaginal clindamycin cream . Patients who were not interested in the programme, served as a control group . 73 out of 381 women in the intervention group were identified as risk cases . In this study, the prematurity rate was 8.1% in the self-measurement/intervention group versus 12.3% in the control group (p < 0.05, n = 2,341); 0.3 versus 3.3% of the neonates belonged to the group of very early prematures with a gestational age of <32 + 0 weeks (p < 0.01) . Starting on March 1, 2000, a similar statewide pH screening programme was initiated in order to reduce prematurity in the State of Thuringia . According to the study design, a significant decrease in prematurity was hypothetically expected for the second half of 2000 . Data from 16,276 women are available . On this basis, a significant reduction of early prematurity from 1.58 to 0.99% was seen (p < 0.001) . Comparing low birth weights, a significant reduction of cases was also achieved in all groups . On the basis of data obtained, we recommend that the campaign should be extended to the whole of Germany . This recommendation is also supported by the observation that after the campaign had been discontinued the prematurity rates monitored in 2002 were as high as they had been prior to the introduction of the statewide programme. Int J Food Microbiol, 2004 Jan 1, 90(1), 93 - 106 The lactobin A and amylovorin L471 encoding genes are identical, and their distribution seems to be restricted to the species Lactobacillus amylovorus that is of interest for cereal fermentations; De Vuyst L et al.; Lactobin A and amylovorin L471 are two bacteriocins produced by the phenotypically different strains Lactobacillus amylovorus LMG P-13139 and L . amylovorus DCE 471, respectively . A 110-bp PCR fragment of the structural gene of lactobin A was obtained from total genomic DNA of L . amylovorus LMG P-13139, which was used as a probe to isolate a 3.6-kb HindIII chromosomal fragment for sequencing . PCR amplification revealed that both the structural genes of both the bacteriocins lactobin A and amylovorin L471 were identical . These bacteriocins will be further referred to as amylovorin L . Amylovorin L can be defined as a small, strongly hydrophobic, antibacterial peptide consisting of 50 amino acids . It is synthesized as a precursor peptide of 65 amino acids processed at a characteristic double-glycine proteolytic cleavage site . Amylovorin L hence belongs to the class II bacteriocins . It has a narrow inhibitory spectrum, being most active towards Lactobacillus delbrueckii subsp . bulgaricus LMG 6901(T) . Among 38 strains of the Lactobacillus acidophilus DNA homology group, another 6 L . amylovorus strains were also inhibitory towards the L . delbrueckii subsp . bulgaricus LMG 6901(T) strain . The lactobin A or amylovorin L471 structural genes could be detected in the genomes of three of these L . amylovorus strains, but only after extensive PCR amplification, indicating that the inhibitory substances were slightly different . The bacteriocins were characterized as small (approximately 4800 Da), heat-stable peptides that were active in a wide pH range (2.2-8.0) . Finally, preliminary experiments indicated that the production of amylovorin L by L . amylovorus DCE 471 took place during a natural rye fermentation, indicating its potential importance in the development of a functional (probiotic) starter culture for cereal fermentations. Int J Food Microbiol, 2004 Jan 1, 90(1), 9 - 14 Lactobacillus casei, dominant species in naturally fermented Sicilian green olives; Randazzo CL et al.; This study investigated the phenotypic and genotypic characteristics of lactic acid bacteria in naturally fermented green olives, collected from different areas of Sicily . Both classical biochemical tests and PCR/Restriction Fragments Length Polymorphism (RFLP) of 16S rDNA were used to characterize the isolates . The identity of the isolates was obtained by the partial sequencing analysis of the 16S rDNA . The BioMerieux software assigned the 13 heterofermentative strains to the Lactobacillus brevis species; 24 homofermentative strains were classified as Lactobacillus casei and the remaining 11 homofermentative lactobacilli were identified as Lactobacillus plantarum . The rapid ID 32 STREP test identified coccal-shaped strains as Enterococcus faecium species . The PCR/RFLP analysis showed a remarkable bacterial heterogeneity within the isolates . The 16S rDNA partial sequencing did not confirm biochemical identification, revealing a strong dominance of isolates belonging to the L . casei species . It is noteworthy that this species has never been reported as dominant species in fermented vegetables.A combination of molecular and biochemical analysis allowed the identification of species involved in natural food fermentations. Artif Cells Blood Substit Immobil Biotechnol, 2003 Nov, 31(4), 425 - 34 Free and microencapsulated Lactobacillus and effects of metabolic induction on urea removal; Chow KM et al.; We have previously reported the experimental use of genetically engineered Escherichia coli with microencapsulation to lower nitrogenous waste . Concern has surfaced, nonetheless, about safety of genetically engineered product . The purpose of this study is to explore the alternative use of probiotics in removal of plasma urea . After repeated cycles of exposure of Lactobacillus delbrueckii in urea-rich medium under anaerobic environment, the organisms were demonstrated to lower plasma urea concentration in vitro . Suspension of Lactobacillus in uremic plasma reduced the urea nitrogen levels from 51.5 +/- 5.2 mg/dL to 44.3 +/- 3.9 mg/dL (P = 0.02) after 24 hours . With microencapsulation of Lactobacillus (inside semipermeable alginate-polylysine-alginate polymeric membrane), further lowering of urea nitrogen levels was achieved (35.4 +/- 0.8 mg/dL, P = 0.03) at 24 hours . These preliminary data show that expression of certain enzymes could be induced in Lactobacillus delbrueckii and thus capable of lowering plasma urea . Further studies and molecular analysis would be indicated to explore and refine the techniques. J Food Prot, 2003 Dec, 66(12), 2313 - 20 Fermentation of Vigna sinensis var . carilla flours by natural microflora and Lactobacillus species; Doblado R et al.; Natural fermentation and an inoculum containing 10% (vol/vol) Lactobacillus fermentum or Lactobacillus plantarum were used to obtain fermented flours from Vigna sinensis L . var . carilla seeds that had been washed with distilled water and dried at 55 degrees C for 24 h . To optimize the fermentation parameters (lactic acid bacterium level, bean flour concentration, and fermentation time), several small-scale fermentation processes were carried out . On the basis of the results obtained, fermentor-scale bean fermentation by microorganisms present on the seeds (natural fermentation {NF}) or by inoculation with L . plantarum (PF) was carried out at 37 degrees C for 48 h with a concentration of 300 g of bean flour per liter . The fermented flours (NF and PF) were also autoclaved . The levels of alpha-galactosides, inositol phosphates, trypsin inhibitor activity (TIA), soluble carbohydrates, starch (total and available), total available carbohydrates, thiamin, and riboflavin were determined for the processed cowpea flours, and microbiological studies were also carried out . The beans' levels of alpha-galactosides, TIA, and inositol hexaphosphate decreased by 95, 50, and 85%, respectively, for the NF flour and by 87, 27, and 85%, respectively, for the PF flour, while inositol pentaphosphate and inositol tetraphosphate were present in both fermented flours . The sucrose content decreased, and glucose, fructose, and galactose appeared as a result of fermentation . The levels of total available sugars and thiamin decreased by 2 and 12% and by 69 and 43%, respectively, while the riboflavin content increased by 106 and 94% for NF and PF flours, respectively . When NF and PF cowpea flours were heated in an autoclave for 20 min, TIA decreased further (by 80 and 56%, respectively) . According to the chemical and microbiological results obtained in this study, fermentation with L . plantarum and autoclaving is an excellent process by which to produce a new functional food from the seed of a cheap legume (Vigna sinensis L . var . carilla). J Dairy Sci, 2003 Nov, 86(11), 3575 - 81 The effect of Lactobacillus buchneri and Lactobacillus plantarum on the fermentation, aerobic stability, and ruminal degradability of low dry matter corn and sorghum silages; Filya I; The effect of Lactobacillus buchneri, alone or in combination with Lactobacillus plantarum, on the fermentation, aerobic stability, and ruminal degradability of low dry matter corn and sorghum silages was studied under laboratory conditions . The inoculants were applied at 1 x 10(6) cfu/g . Silages with no additives served as control . After treatment, the chopped forages were ensiled in 1.5-L anaerobic jars . Three jars per treatment were sampled on d 2, 4, 8, 15, and 90 . After 90 d of storage, the silages were subjected to an aerobic stability test lasting 5 d, in which CO2 production, as well as chemical and microbiological parameters, was measured to determine the extent of aerobic deterioration . At the end of the ensiling period (d 90), the L . buchneri- and L . buchneri + L . plantarum-inoculated silages had significantly higher levels of acetic acid than the control and L . plantarum-inoculated silages . Therefore, yeast activity was impaired in the L . buchneri- and L . buchneri + L . plantarum-inoculated silages . As a result, L . buchneri, alone or in combination with L . plantarum, improved aerobic stability of the low dry matter corn and sorghum silages . The combination of L . buchneri and L . plantarum reduced ammonia N concentrations and fermentation losses in the silages compared with L . buchneri alone . However, L . buchneri, L . plantarum, and a combination of L . buchneri + L . plantarum did not effect in situ rumen dry matter, organic matters, or neutral detergent fiber degradability of the silages . The L . buchneri was very effective in protecting the low dry matter corn and sorghum silages exposed to air under laboratory conditions . The use of L . buchneri, alone or in combination with L . plantarum, as a silage inoculant can improve the aerobic stability of low dry matter corn and sorghum silages by inhibition of yeast activity. Curr Microbiol, 2003 Nov, 47(5), 395 - 9 Sequencing and characterization of plasmid pUIBI-1 from Bacillus thuringiensis serovar entomocidus LBIT-113; Lopez-Meza JE et al.; Plasmid pUIBI-1 from Bacillus thuringiensis svr . entomocidus was sequenced and its replication mechanism analyzed . Sequence analysis revealed that pUIBI-1 contains 4671 bp and a 32% GC content . Plasmid pUIBI-1 also includes at least seven putative open reading frames (ORFs) encoding for proteins ranging from 5 to 50 kDa . ORF-1 encodes for a putative 16-kDa Rep protein, which lacks homology with proteins of similar function . ORF2 encodes for a protein of 50 kDa and shows homology with Mob proteins of plasmids pLUB1000 from Lactobacillus hilgardii (32.2%) and pGI2 from B . thuringiensis (33.7%) . Detection of single-stranded DNA (ssDNA) intermediates indicated that pUIBI-1 replicates by the rolling-circle replication mechanism, as demonstrated by S1 treatment and Southern hybridization under non-denaturing conditions. Appl Microbiol Biotechnol, 2004 Mar, 64(1), 16 - 27 Epub 2003 Dec 11. 3-hydroxypropionaldehyde: applications and perspectives of biotechnological production; Vollenweider S et al.; 3-hydroxypropionaldehyde (3-HPA) forms, together with HPA-hydrate and HPA-dimer, a dynamic, multi-component system (HPA system) used in food preservation, as a precursor for many modern chemicals such as acrolein, acrylic acid, and 1,3-propanediol (1,3-PDO), and for polymer production . 3-HPA can be obtained both through traditional chemistry and bacterial fermentation . To date, 3-HPA has been produced from petrochemical resources as an intermediate in 1,3-PDO production . In vivo, glycerol is converted in one enzymatic step into 3-HPA . The 3-HPA-producing Lactobacillus reuteri is used as a probiotic in the health care of humans and animals . The biotechnological production of 3-HPA from renewable resources is desirable both for use of 3-HPA in foods and for the production of bulk chemicals . The main challenge will be the efficient production and recovery of pure 3-HPA. Syst Appl Microbiol, 2003 Nov, 26(4), 546 - 56 Identification of Carnobacterium, Lactobacillus, Leuconostoc and Pediococcus by rDNA-based techniques; Chenoll E et al.; Ribosomal DNA-based techniques including the analysis of profiles generated by ISR amplification, ISR restriction and ARDRA have been evaluated as molecular tools for identifying Carnobacterium, Lactobacillus, Leuconostoc and Pediococcus . They have been applied for the molecular characterization of 91 strains with the following identities: eight Carnobacterium including the eight type species of the genus; 61 Lactobacillus including 40 type strains out of 45 species, 13 Leuconostoc, out of them 11 are type strains and three are subspecies of Lc . mesenteroides; and nine strains representing the six species of genus Pediococcus . The genetic relationship displayed between these species by rrn-based profiles is sustained by their phylogenetic relationships and can therefore be considered useful for taxonomic purposes . Profiles obtained by ISR amplification allowed identification at genus level of Carnobacterium and Leuconostoc, and even at species level in genus Carnobacterium . Genera Lactobacillus and Pediococcus could not be distinguished from each other by applying this technique . The Lactobacillus species analysed here (45) were differentiated using ARDRA-DdeI and ISR-DdeI profiles, sequentially, and Pediococcus species by ISR-DdeI profiles . It was necessary to combine profiles generated by restriction of ISR-DdeI, ARDRA-DdeI and ARDRA-HaeIII in order to complete the identification of Leuconostoc species. Microbiology, 2003 Dec, 149(Pt 12), 3493 - 505 Phage display reveals 52 novel extracellular and transmembrane proteins from Lactobacillus reuteri DSM 20016(T); Wall T et al.; Extracellular and transmembrane proteins are important for the binding of bacteria to intestinal surfaces and for their interaction with the host . The aim of this study was to identify genes encoding extracellular and transmembrane proteins from the probiotic bacterium Lactobacillus reuteri by construction and screening of a phage display library . This library was constructed by insertion of randomly fragmented DNA from L . reuteri into the phagemid vector pG3DSS, which was previously developed for screening for extracellular proteins . After affinity selection of the library, the L . reuteri inserts were sequenced and analysed with bioinformatic tools . The screening resulted in the identification of 52 novel genes encoding extracellular and transmembrane proteins . These proteins were classified as: transport proteins; enzymes; sensor-regulator proteins; proteins involved in host/microbial interactions; conserved hypothetical proteins; and unconserved hypothetical proteins . Further characterization of the extracellular and transmembrane proteins identified should contribute to the understanding of the probiotic properties of L . reuteri. Appl Environ Microbiol, 2003 Dec, 69(12), 7554 - 7 Antifungal 3-hydroxy fatty acids from Lactobacillus plantarum MiLAB 14; Sjogren J et al.; We report the identification and chemical characterization of four antifungal substances, 3-(R)-hydroxydecanoic acid, 3-hydroxy-5-cis-dodecenoic acid, 3-(R)-hydroxydodecanoic acid and 3-(R)-hydroxytetradecanoic acid, from Lactobacillus plantarum MiLAB 14 . The concentrations of the 3-hydroxy fatty acids in the supernatant followed the bacterial growth . Racemic mixtures of the saturated 3-hydroxy fatty acids showed antifungal activity against different molds and yeasts with MICs between 10 and 100 micrograms ml-1. Appl Environ Microbiol, 2003 Dec, 69(12), 7194 - 203 Functional characterization of a composite bacteriocin locus from malt isolate Lactobacillus sakei 5; Vaughan A et al.; Lactobacillus sakei 5, isolated from malted barley, produces three bacteriocins . Genetic and functional analysis of the purified bacteriocins showed that this strain produces a plasmid-encoded bacteriocin that is identical to sakacin P, as well as two novel, chromosomally encoded bacteriocins, which were designated sakacin T and sakacin X . The structural genes specifying sakacin T and sakacin X are part of the sakacin TX locus, which consists of two adjacent but divergently oriented gene clusters . The first gene cluster includes stxP, stxR, stxK, and stxT, which, based on functional and comparative sequence analysis, are believed to encode an inducing peptide and proteins involved in regulation and secretion of these bacteriocins . The second gene cluster includes the structural and immunity genes for sakacin T, a class IIb two-peptide bacteriocin composed of SakTalpha and SakTbeta, and sakacin X, a class IIa bacteriocin . Interestingly, a so-called transport accessory protein was absent from the locus, and based on our results it appears that a dedicated accessory protein is not required for processing and transport of sakacin T and sakacin X. Appl Environ Microbiol, 2003 Dec, 69(12), 7173 - 80 Heat shock treatment increases the frequency of loss of an erythromycin resistance-encoding transposable element from the chromosome of Lactobacillus crispatus CHCC3692; Stroman P et al.; A 3,165-bp chromosomally integrated transposon, designatedTn3692, of the gram-positive strain Lactobacillus crispatus CHCC3692 contains an erm(B) gene conferring resistance to erythromycin at concentrations of up to 250 micrograms/ml . Loss of this resistance can occur spontaneously, but the rate is substantially increased by heat shock treatment . Heat shock treatment at 60 degrees C resulted in an almost 40-fold increase in the frequency of erythromycin-sensitive cells (erythromycin MIC, 0.047 micrograms/ml) . The phenotypic change was followed by a dramatic increase in transcription of the transposase gene and the concomitant loss of an approximately 2-kb DNA fragment carrying the erm(B) gene from the 3,165-bp erm transposon . In cells that were not subjected to heat shock, transcription of the transposase gene was not detectable . The upstream sequence of the transposase gene did not show any homology to known heat shock promoters in the gene data bank . Significant homology (>99%) was observed between the erythromycin resistance-encoding gene from L . crispatus CHCC3692 and the erm(B) genes from other gram-positive bacteria, such as Streptococcus agalactiae, Streptococcus pyogenes, Enterococcus faecium, and Lactobacillus reuteri, which strongly indicates a common origin of the erm(B) gene for these species . The transposed DNA element was not translocated to other parts of the genome of CHCC3692, as determining by Southern blotting, PCR analysis, and DNA sequencing . No other major aberrations were observed, as judged by colony morphology, growth performance of the strain, and pulsed-field gel electrophoresis . These observations suggest that heat shock treatment could be used as a tool for the removal of unwanted antibiotic resistance genes harbored in transposons flanked by insertion sequence elements or transposases in lactic acid bacteria used for animal and human food production. FEMS Microbiol Lett, 2003 Dec 5, 229(1), 141 - 4 Ribotyping of lactobacilli isolated from spoiled beer; Yansanjav A et al.; Twenty-nine Lactobacillus strains contaminating beers in different Czech breweries as well as representative type strains obtained from the Czech Collection of Microorganisms were characterized using ribotyping with EcoRI and a probe made complementary to 16S and 23S rRNA genes . Biochemical test results assigned the 29 strains to the species L . brevis, L . plantarum, L . buchneri and L . paracasei subsp . paracasei . Ribotyping separated L . brevis, L . plantarum and L . paracasei subsp . paracasei strains into species-specific ribogroups in full correspondence with biotyping; L . buchneri strains were split into two ribogroups . Characteristic band patterns for each species and even typical bands of certain sizes were observed. FEMS Microbiol Lett, 2003 Dec 5, 229(1), 119 - 26 Construction of vectors for inducible gene expression in Lactobacillus sakei and L plantarum; Sorvig E et al.; We have constructed vectors for inducible expression of genes in Lactobacillus sakei and Lactobacillus plantarum . The key elements of these vectors are a regulatable promoter involved in the production of the bacteriocins sakacin A and sakacin P and the genes encoding the cognate histidine protein kinase and response regulator that are necessary to activate this promoter upon induction by a peptide pheromone . The vectors are built up of cassettes that permit easy exchange of all parts through restriction enzyme digestion and ligation . Using beta-glucuronidase as a reporter enzyme, variants of these vectors were compared with each other, and with a corresponding system based on genes involved in the production of nisin . Several of the new vectors permitted tightly controlled and efficient expression of beta-glucuronidase in both L . sakei and L . plantarum. J Pediatr, 2003 Dec, 143(6), 754 - 8 Human milk is a source of lactic acid bacteria for the infant gut; Martin R et al.; OBJECTIVES: To investigate whether human breast milk contains potentially probiotic lactic acid bacteria, and therefore, whether it can be considered a synbiotic food.Study design Lactic acid bacteria were isolated from milk, mammary areola, and breast skin of eight healthy mothers and oral swabs and feces of their respective breast-fed infants . Some isolates (178 from each mother and newborn pair) were randomly selected and submitted to randomly amplified polymorphic DNA (RAPD) polymerase chain reaction analysis, and those that displayed identical RAPD patterns were identified by 16S rDNA sequencing . RESULTS: Within each mother and newborn pair, some rod-shaped lactic acid bacteria isolated from mammary areola, breast milk, and infant oral swabs and feces displayed identical RAPD profiles . All of them, independently from the mother and child pair, were identified as Lactobacillus gasseri . Similarly, among coccoid lactic acid bacteria from these different sources, some shared an identical RAPD pattern and were identified as Enterococcus faecium . In contrast, none of the lactic acid bacteria isolated from breast skin shared RAPD profiles with lactic acid bacteria of the other sources . CONCLUSIONS: Breast-feeding can be a significant source of lactic acid bacteria to the infant gut . Lactic acid bacteria present in milk may have an endogenous origin and may not be the result of contamination from the surrounding breast skin. Int J Syst Evol Microbiol, 2003 Nov, 53(Pt 6), 2055 - 9 Lactobacillus kitasatonis sp . nov., from chicken intestine; Mukai T et al.; Four strains isolated from chicken small intestine and strains JCM 1038 and JCM 1039 (designated as Lactobacillus acidophilus) were characterized by phenotypic and molecular taxonomic methods . They were Gram-positive, catalase-negative, facultatively anaerobic rods that did not produce gas from glucose . These strains had similar phenotypic characteristics and exhibited intergroup DNA relatedness values of >77 %, indicating that they comprised a single species . The 16S rRNA gene sequence of a representative strain, JCM 1039(T) (designated as type strain in this study), was determined and aligned with those of other Lactobacillus species . JCM 1039(T) was placed in the Lactobacillus delbrueckii cluster of the genus Lactobacillus on the basis of phylogenetic analysis and formed an independent cluster that was distinct from its closest neighbours, Lactobacillus amylovorus, Lactobacillus crispatus, Lactobacillus gallinarum, L . acidophilus and Lactobacillus helveticus . Results of DNA-DNA hybridization experiments and whole-cell protein profiles clearly indicated that these strains represent a novel Lactobacillus species, for which the name Lactobacillus kitasatonis sp . nov . is proposed; the type strain of this species is JCM 1039(T). Biotechnol Prog, 2003 Nov-Dec, 19(6), 1816 - 21 Assessment of in-line near-infrared spectroscopy for continuous monitoring of fermentation processes; Tosi S et al.; The application of NIR in-line to monitor and control fermentation processes was investigated . Determination of biomass, glucose, and lactic and acetic acids during fermentations of Staphylococcus xylosus ES13 was performed by an interactance fiber optic probe immersed into the culture broth and connected to a NIR instrument . Partial least squares regression (PLSR) calibration models of second derivative NIR spectra in the 700-1800 nm region gave satisfactory predictive models for all parameters of interest: biomass, glucose, and lactic and acetic acids . Batch, repeated batch, and continuous fermentations were monitored and automatically controlled by interfacing the NIR to the bioreactor control unit . The high frequency of data collection permitted an accurate study of the kinetics, supplying lots of data that describe the cultural broth composition and strengthen statistical analysis . Comparison of spectra collected throughout fermentation runs of S . xylosus ES13, Lactobacillus fermentum ES15, and Streptococcus thermophylus ES17 demonstrated the successful extension of a unique calibration model, developed for S . xylosus ES13, to other strains that were differently shaped but growing in the same medium and fermentation conditions . NIR in-line was so versatile as to measure several biochemical parameters of different bacteria by means of slightly adapted models, avoiding a separate calibration for each strain. Berl Munch Tierarztl Wochenschr, 2003 Nov-Dec, 116(11-12), 510 - 6 {Use of molecular methods in food microbiology with the example of probiotic use of lactobacilli}; Klein G; The aim of molecular methods in food microbiology is the identification or strain specific differentiation of microorganisms . Identification methods include besides taxonomic purposes also the detection of virulence genes or resistance markers . Strain specific differentiation is used for epidemiological investigations or the quality control of technologically used bacteria . Probiotic strains of the Lactobacillus acidophilus-group were investigated with different molecular methods: for identification proteinfingerprinting and RAPD-PCR (Random Amplified Polymorphic DNA-PCR) were applied, for strain specific differentiation pulsed field gel electrophoresis (PFGE) and again RAPD-PCR were used . The molecular methods applied should be chosen depending on the objective (identification, differentiation) and with respect to the organism to be tested . In case of probiotic lactic acid bacteria like the L . acidophilus-group proteinfingerprinting has proved to be successful for identification and with some limitation also RAPD-PCR . For differentiation PFGE is suitable as well as RAPD-PCR . Those methods differ substantially in their work load and in personal requirements, and show different power of discrimination and reproducibility within and between laboratories . This should be considered while choosing the appropriate method. Biophys J, 2003 Dec, 85(6), 4076 - 92 The cell wall of lactic acid bacteria: surface constituents and macromolecular conformations; Schar-Zammaretti P et al.; A variety of strains of the genus Lactobacillus was investigated with respect to the structure, softness, and interactions of their outer surface layers in order to construct structure-property relations of the Gram-positive bacterial cell wall . The role of the conformational properties of the constituents of the outer cell-wall layers and their spatial distribution on the cell wall is emphasized . Atomic force microscopy was used to resolve the surface structure, interactions, and softness of the bacterial cell wall at nanometer-length scales and upwards . The pH-dependence of the electrophoretic mobility and a novel interfacial adhesion assay were used to analyze the average physicochemical properties of the bacterial strains . The bacterial surface is smooth when a compact layer of globular proteins constitutes the outer surface, e.g., the S-layer of L . crispatus DSM20584 . In contrast, for two other S-layer containing strains (L . helveticus ATCC12046 and L . helveticus ATCC15009), the S-layer is covered by polymeric surface constituents which adopt a much more extended conformation and which confer a certain roughness to the surface . Consequently, the S-layer is important for the overall surface properties of L . crispatus, but not for the surface properties of L . helveticus . Both surface proteins (L . crispatus DSM20584) and (lipo)teichoic acids (L . johnsonii ATCC332) confer hydrophobic properties to the bacterial surface whereas polysaccharides (L . johnsonii DSM20533 and L . johnsonii ATCC 33200) render the bacterial surface hydrophilic . Using the interfacial adhesion assay, it was demonstrated that hydrophobic groups within the cell wall adsorb limited quantities of hydrophobic compounds . The present work demonstrates that the impressive variation in surface properties displayed by even a limited number of genetically-related bacterial strains can be understood in terms of established colloidal concepts, provided that sufficiently detailed structural, chemical, and conformational information on the surface constituents is available. Bioresour Technol, 2004 Mar, 92(1), 1 - 6 Screening for yeast with antibacterial properties from an ethanol distillery; de Oliva Neto P et al.; A general screening for the expression of antibacterial activity and non-flocculating type of yeast strains from must and fermented broth of alcohol distilleries was performed . From 60 strains only Saccharomyces sp . M26 presented a inhibitory halo in Lactobacillus fermentum culture and significant reduction in the culture turbidity (71%) and specific growth rate (56%) when compared to the control . Freezing did not affect the antibacterial activity of the Saccharomyces sp . M26 extract and heating at 90 degrees C for 20 min completely destroyed this activity . It is expected the decrease of lactic acid bacteria growth in the S . cerevisiae alcoholic fermentation should allow for better control of these bacteria in the process. Res Microbiol, 2003 Dec, 154(10), 705 - 12 Isolation and characterization of two exopolysaccharides produced by Lactobacillus plantarum EP56; Tallon R et al.; A Lactobacillus plantarum strain producing exopolysaccharides (EPSs) was isolated from corn silage . When this strain, named L . plantarum EP56, was grown on a chemically defined medium, two EPS fractions were isolated . The cell-bound EPS fraction (EPS-b) was composed of a single high-molecular-mass polymer of 8.5x10(5) Da containing glucose, galactose and N-acetylgalactosamine in a molar ratio of approximately 3:1:1 and traces of glycerol and phosphoglycerol . The released EPS fraction (EPS-r) was composed of the high-molecular-mass bound polysaccharide and a second polymer of 4x10(4) Da containing glucose, galactose and rhamnose in a molar ratio of 3:1:1 and traces of glycerol and phosphoglycerol . EPS-b and EPS-r contained phosphate which contributes to their negative net charge . Studies on polysaccharide production and location showed that both polymers were synthesized during the exponential growth phase and that the EPS-b polymer was progressively released into the culture medium during the stationary growth phase . Carbon source and temperature influenced EPS synthesis when L . plantarum EP56 was grown in a chemically defined medium . Lactose was the most efficient carbon source among the five tested (glucose, galactose, fructose, lactose and sucrose) . EPS production was also increased when the incubation temperature is lowered. Res Microbiol, 2003 Dec, 154(10), 669 - 75 Antagonistic interactions among Fusobacterium nucleatum and Prevotella intermedia with oral lactobacilli; Testa MM et al.; Microbiota residing in oral ecosystems show great complexity because of the mutual interdependence of certain microorganisms that might influence their presence or absence at a given site . The aim of this work was to evaluate possible antagonistic interactions among Fusobacterium nucleatum and Prevotella intermedia, isolated from periodontal pockets, and Lactobacillus casei, L . salivarius, L . rhamnosus and L . plantarum isolated from saliva . Different tests were carried out using each strain as an effector as well as a sensitive strain, alternatively: (1) agar diffusion with paper disks embedded with supernatants and pellets in different culture media; (b) the well diffusion assay; (c) the double layer method; and (d) OD(560) measurements of the kinetic growth of Lactobacillus strains in LAPTg broth with different volumes of F . nucleatum supernatant . P . intermedia supernatant did not have an inhibitory effect on Lactobacillus growth, except for L . casei, when the double plaque method was used . F . nucleatum supernatant inhibited growth of all Lactobacillus strains when the well diffusion method was used . F . nucleatum inhibited L . casei growth whatever the method used . The substance responsible for inhibition was a thermoresistant extracellular protein which was hydrolyzed by trypsin-like proteases . None of the species of lactobacilli studied inhibited the growth of P . intermedia or F . nucleatum. Isr Med Assoc J, 2003 Nov, 5(11), 767 - 9 Vaginal colonization by orally administered Lactobacillus rhamnosus GG; Colodner R et al.; BACKGROUND: The lack of lactobacilli in the vagina of postmenopausal women due to estrogen deficiency plays an important role in the development of bacteriuria . In the last few years the use of lactobacilli for the prevention of genitourinary infections has been explored using different probiotic strains . OBJECTIVES: To evaluate the vaginal colonization by Lactobacillus rhamnosus GG in postmenopausal healthy women following oral administration of the bacteria in a yogurt base for 1 month, as a first step in evaluating the potential probiotic role of LGG in the prevention of recurrent urinary tract infections . METHODS: One or two doses per day of yogurt containing 10(9) colony-forming units of LGG were administered orally to 42 postmenopausal healthy women for 1 month . Vaginal and rectal swabs were cultured at the beginning and end of the study . RESULTS: At the end of the study the vaginas of only four women (9.5%) were colonized with LGG, at a very low number of bacteria, despite the fact that the gastrointestinal tracts of 33 women (78.6%) were colonized . There were no significant differences between one or two doses daily . CONCLUSIONS: LGG should not be considered as a probiotic agent in urinary infections since it does not attach well to the vaginal epithelium. J Dairy Res, 2003 Nov, 70(4), 433 - 40 Probiotics induce resistance to enteropathogens in a re-nourished mouse model; Cano PG et al.; Nutritional deficiency is commonly associated with impaired immune response and the relation between infection and malnutrition is synergic . Probiotics, especially lactic acid bacteria are immunomodulatory . The aim was to determine whether optimal doses of Lactobacillus casei and yogurt, used as adjuvants in a re-nutrition diet in a non-severe malnutrition experimental model, protect against Salmonella typhimurium and Escherichia coli . Groups of malnourished mice were used, which were re-nourished with milk for 7 or 14 d . After that, both groups of mice received the optimal doses of Lb . casei and yogurt supplements . We measured IgA+ and IgG+-B cells and phenotypic markers of T lymphocytes; CD3+, CD4+ and CD8+ cells . We also determined alphabeta and gammabeta T cell receptor (TCR) . The ability to protect against Sal . typhimurium and Esch . coli infections and specific S-IgA were assessed . Probiotics complemented the effects of the re-nutrition diet, by stimulating recuperation of the activity of immune cells that improved protection against infections. Arch Microbiol, 2004 Jan, 181(1), 8 - 16 Epub 2003 Nov 29. Production of plantaricin NC8 by Lactobacillus plantarum NC8 is induced in the presence of different types of gram-positive bacteria; Maldonado A et al.; Lactobacillus plantarum NC8 was shown to produce plantaricin NC8 (PLNC8), a recently purified and genetically characterized inducible class IIb bacteriocin, only when it was co-cultured with other gram-positive bacteria . Among 82 strains belonging to the genera Bacillus, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Listeria, Pediococcus, Staphylococcus, and Streptococcus, 41 were shown to induce PLNC8 production in L . plantarum NC8 . There was apparently no relationship between the sensitivity of the strains and their ability to induce the bacteriocin, indicating that the inducer and sensitive phenotypes may not be linked . In some instances, induction was promoted by both living and heat-killed cells of the inducing bacteria . However, no PLNC8-inducing activity was found in the respective cell-free, pure culture supernatants . Inducer strains also promoted the production of a PLNC8-autoinducing activity by L . plantarum NC8, which was found only in the cell-free co-culture supernatants showing inhibitory activity . This PLNC8-autoinducing activity was diffusible, heat resistant, and of a proteinaceous nature, and was different from the bacteriocin itself . Taken together, the results suggest that the presence of specific gram-positive bacteria acts as an environmental stimulus activating both PLNC8 production by L . plantarum NC8 and a PLNC8-autoinducing activity, which in turn triggers or maintains bacteriocin production in the absence of inducing cells. Virology, 2003 Nov 25, 316(2), 245 - 55 The prophage sequences of Lactobacillus plantarum strain WCFS1; Ventura M et al.; The Lactobacillus plantarum commensal WCFS1 contains four prophage elements in its genome . Lp1 and Lp2 are two about 40-kb-long uninducible prophages that share closely related DNA packaging, head and tail genes defining a second lineage of pac-site Siphoviridae in L . plantarum, distinct from L . plantarum phage phig1e, but related to Bacillus phage SPP1 and Lactococcus phage TP901-1 . Northern analysis revealed transcribed prophage genes exclusively near both attachment sites . Comparative genomics identified candidate lysogenic conversion genes (LCG) downstream of the lysis cassette and within the lysogeny module . Notable are genes with sequence similarities to putative LCG from Streptococcus pyogenes prophages and to a Bacillus plasmid . Both prophages harbored tRNA genes . R-Lp3 and R-Lp4 represent short prophage remnants; R-Lp3 abuts Lp2 and displays sequence links to cos-site Siphoviridae. Environ Microbiol, 2003 Nov, 5(11), 1071 - 86 Diverse microbial communities inhabiting ferromanganese deposits in Lechuguilla and Spider Caves; Northup DE et al.; Lechuguilla Cave is an ancient, deep, oligotrophic subterranean environment that contains an abundance of low-density ferromanganese deposits, the origin of which is uncertain . To assess the possibility that biotic factors may be involved in the production of these deposits and to investigate the nature of the microbial community in these materials, we carried out culture-independent, small subunit ribosomal RNA (SSU rRNA) sequence-based studies from two sites and from manganese and iron enrichment cultures inoculated with ferromanganese deposits from Lechuguilla and Spider Caves . Sequence analysis showed the presence of some organisms whose closest relatives are known iron- and manganese-oxidizing/reducing bacteria, including Hyphomicrobium, Pedomicrobium, Leptospirillum, Stenotrophomonas and Pantoea . The dominant clone types in one site grouped with mesophilic Archaea in both the Crenarchaeota and Euryarchaeota . The second site was dominated almost entirely by lactobacilli . Other clone sequences were most closely related to those of nitrite-oxidizing bacteria, nitrogen-fixing bacteria, actinomycetes and beta- and gamma-Proteobacteria . Geochemical analyses showed a fourfold enrichment of oxidized iron and manganese from bedrock to darkest ferromanganese deposits . These data support our hypothesis that microorganisms may contribute to the formation of manganese and iron oxide-rich deposits and a diverse microbial community is present in these unusual secondary mineral formations. Biochem Biophys Res Commun, 2003 Dec 12, 312(2), 285 - 91 Lactic acid bacteria as prime candidates for codon optimization; Fuglsang A; In species having a strong correlation of expressivity and codon bias it has been shown that heterologous expression can be optimized by changing codons of the introduced gene towards the set of codons that the host organism naturally uses in its highly expressed genes . Even though two lactic acid bacteria are fully sequenced, there are no reports on attempts of codon optimization in the literature . In this report it is demonstrated that codons used in highly expressed genes tend to differ from the codons in lowly expressed genes, and that there is a strong correlation of codon bias and empirical expressivity (codon adaptation index) in Lactococcus lactis and Lactobacillus plantarum . This strongly suggests that codon optimization strategies could be applied to expression systems with lactic acid bacteria as producer strains . A good example of a candidate for codon optimization is the mouse interleukin-2 gene, which in its natural form has an extremely low codon adaptation index for expression in Lc . lactis. J Appl Microbiol, 2003, 95(5), 1080 - 6 The effect of Lactobacillus buchneri, with or without homofermentative lactic acid bacteria, on the fermentation, aerobic stability and ruminal degradability of wheat, sorghum and maize silages; Filya I; AIMS: To determine the effect of Lactobacillus buchneri, alone or in combination with homofermentative lactic acid bacteria (LAB), on the fermentation, aerobic stability and ruminal degradability of wheat, sorghum and maize silages . METHODS AND RESULTS: The inoculants were applied at 1.0 x 10(6) CFU g(-1) . Silages with no additives served as control . Three jars per treatment were sampled on days 2, 4, 8, 15 and 60 after ensiling, for chemical and microbiological analysis . At the end of the ensiling period, the silages were subjected to an aerobic stability test . The L . buchneri- and L . buchneri + L . plantarum-inoculated silages had significantly higher levels of acetic acid than the control and L . plantarum-inoculated silages (P<0.05) . Therefore, yeast activity was impaired in the L . buchneri- and L . buchneri + L . plantarum-inoculated silages . As a result, L . buchneri, with or without L . plantarum, improved aerobic stability of the silages . The combination of L . buchneri and L . plantarum reduced pH, ammonia-N, and fermentation losses in the silages . However, L . buchneri, L . plantarum and L . buchneri + L . plantarum did not affect in situ dry matter, organic matters, and neutral detergent fibre degradability of the silages . CONCLUSIONS: The L . buchneri was very effective in protecting the wheat, sorghum and maize silages exposed to air under laboratory conditions . SIGNIFICANCE AND IMPACT OF THE STUDY: The use of L . buchneri, with or without homofermentative LAB, as a silage inoculant can improve the aerobic stability of silages by inhibition of yeast activity. J Appl Microbiol, 2003, 95(5), 1049 - 57 Exopolysaccharide production during batch cultures with free and immobilized Lactobacillus rhamnosus RW-9595M; Bergmaier D et al.; AIMS: Exopolysaccharides (EPS) were produced by Lactobacillus rhamnosus RW-9595M during pH-controlled batch cultures with free cells and repeated-batch cultures with cells immobilized on solid porous supports (ImmobaSil) . METHODS AND RESULTS: Cultures were conducted in supplemented whey permeate (SWP) medium containing 5 or 8% (w/w) whey permeate . For free-cell batch cultures in 8% SWP medium, very high maximum cell counts (1.3 x 10(10) CFU ml(-1)) and EPS production (2350 mg l(-1)) were measured . A high EPS production (1750 mg l(-1)) was measured after four cycles for a short incubation period of only 7 h . Several methods for immobilized biomass determination based on analysis of biomass components (proteins, ATP and DNA) were tested . The DNA analysis method proved to be the most appropriate under these circumstances . This method revealed a high maximum immobilized biomass of 8.5 x 10(11) CFU ml(-1) support during repeated immobilized cell cultures in 5% SWP . The high immobilized biomass increased maximum EPS volumetric productivity (250 mg l(-1) h(-1) after 7 h culture) compared with free-cell batch cultures (110 mg l(-1) h(-1) after 18 h culture) . CONCLUSIONS: High EPS productions were achieved during batch cultures of Lact . rhamnosus RW-9595M in SWP medium, exceeding 1.7 g EPS per litre . Repeated-batch cultures with immobilized cells resulted in increased EPS productivity compared with traditional free-cell cultures . SIGNIFICANCE AND IMPACT OF THE STUDY: The study clearly shows the high potential of the strain Lact . rhamnosus RW-9595M and immobilized cell technology for production of EPS as a functional food ingredient. J Appl Microbiol, 2003, 95(5), 921 - 33 Multiple competitive PCR-DGGE as a tool for quantifying and profiling defined mixed cultures of lactic acid bacteria during production of probiotics from complex polysaccharides; Pintado J et al.; AIMS: To apply a denaturing gradient gel electrophoretic (DGGE) method to quantify and profile individual strains during a mixed culture fermentation . METHODS AND RESULTS: DNA was extracted during the culture of lactic acid bacteria (LAB) and amplified in a multiple competitive PCR (cPCR) using general primers targeting 16S rDNA and DNA from Streptococcus salivarius as competitive DNA . Subsequently the 200-kb amplified fragments were separated by DGGE . The method was validated in pure cultures and used to profile a mixture of three LAB grown on glucose, soluble starch and glycogen from mussel processing waste . The inclusion of a starch- and glycogen-degrading strain (Lactobacillus plantarum) and a weakly amylotic nisin-resistant strain (Lact . paracasei) allowed proliferation of the nisin producing Lactococcus lactis which in itself is unable to grow on complex carbohydrates . cPCR-DGGE permitted the monitoring of a different strain succession on the different carbohydrates, related to amylolytic activity and substrate consumption, acid production and nisin production . CONCLUSIONS: cPCR-DGGE is a useful tool for profiling defined mixed cultures of bacteria and hence allows their interaction to be studied . SIGNIFICANCE AND IMPACT OF THE STUDY: Provided validation of the method for each specific case, it may be appropriate to monitor and control the reproducibility of any defined mixed culture of bacteria, with the advantage that an increase in the strain numbers to be monitored does not yield an increase in the labour of the procedure. J Appl Microbiol, 2003, 95(6), 1315 - 20 Action of trehalose on the preservation of Lactobacillus delbrueckii ssp . bulgaricus by heat and osmotic dehydration; Gomez Zavaglia A et al.; AIM: This work determines the efficiency of trehalose on the preservation by heat or osmotic drying of a strain of Lactobacillus delbrueckii ssp . bulgaricus . Cell recovery at different trehalose concentrations during drying correlated with the surface properties and osmotic response of cells after rehydration . METHODS AND RESULTS: Bacteria were dried in the presence of glycerol, trehalose, sucrose at 70 degrees C and at 20 degrees C . Trehalose attenuates the loss of viability at 0.25 m . At this concentration, the osmotic response and zeta potential of the bacteria were comparable with the nondried ones . CONCLUSIONS: Trehalose diminishes significantly the damage produced by dehydration both when the bacteria are dried by heating or subjected to osmotic dehydration . This effect appears related to the preservation of the permeability to water and the surface potential of the bacteria . SIGNIFICANCE AND IMPACT OF THE STUDY: Dehydration occurring during heating or during osmosis appears to have similar effects . As dehydration-induced damage is in correlation with osmotic response recovery and is hindered or buffered by the presence of trehalose, it may be related to water eliminated from biological structures involved in water permeation. J Appl Microbiol, 2003, 95(6), 1255 - 60 Rapid determination of vitamin B2 secretion by bacteria growing on solid media; Salvetti S et al.; AIMS: Development of an agar-diffusion assay to measure vitamin B2 in biological samples and application of the method to determine the amount of vitamin B2 secreted by bacteria . METHODS AND RESULTS: A riboflavin-auxotrophic mutant of Bacillus cereus was generated by mini-Tn10 insertion in the ribD gene . ribD mutant sensitivity to exogenous vitamin B2 was investigated by turbidimetric and agar-diffusion assays . In turbidimetric assays, the B . cereus mutant displayed a similar level of sensitivity to vitamin B2 to that of Lactobacillus casei ATCC 7469, the reference organism used for microbiological vitamin B2 quantification . However, only the ribD mutant could be used as an indicator organism in agar-diffusion assays . A total of eight probiotic strains, from five different probiotic formulations, were analysed by the ribD mutant-based assay on agar plates in order to determine their ability to secrete vitamin B2 during growth . CONCLUSION: The agar diffusion method with the ribD mutant of B . cereus is highly reproducible, sensitive, rapid, inexpensive, and can be applied to measure the amount of vitamin B2 in different samples . SIGNIFICANCE AND IMPACT OF THE STUDY: The method developed in this study appears to be a good candidate for the screening of vitamin B2 secretion by bacteria growing on solid media. J Appl Microbiol, 2003, 95(6), 1207 - 16 Identification of Lactobacillus alimentarius and Lactobacillus farciminis with 16S-23S rDNA intergenic spacer region polymorphism and PCR amplification using species-specific oligonucleotide; Rachman CN et al.; AIMS: The restriction fragment length polymorphism (RFLP) method was used to differentiate Lactobacillus species having closely related identities in the 16S-23S rDNA intergenic spacer region (ISR) . Species-specific primers for Lact . farciminis and Lact . alimentarius were designed and allowed rapid identification of these species . METHODS AND RESULTS: The 16S-23S rDNA spacer region was amplified by primers tAla and 23S/p10, then digested by HinfI and TaqI enzymes and analysed by electrophoresis . Digestion by HinfI was not sufficient to differentiate Lact . sakei, Lact . curvatus, Lact . farciminis, Lact . alimentarius, Lact . plantarum and Lact . paraplantarum . In contrast, digestion carried out by TaqI revealed five different patterns allowing these species to be distinguished, except for Lact . plantarum from Lact . paraplantarum . The 16S-23S rDNA spacer region of Lact . farciminis and Lact . alimentarius were amplified and then cloned into vector pCR(R)2.1 and sequenced . The DNA sequences obtained were analysed and species-specific primers were designed from these sequences . The specificity of these primers was positively demonstrated as no response was obtained for 14 other species tested . RESULTS AND CONCLUSIONS: The species-specific primers for Lact . farciminis and Lact . alimentarius were shown to be useful for identifying these species among other lactobacilli . The RFLP profile obtained upon digestion with HinfI and TaqI enzymes can be used to discriminate Lact . farciminis, Lact . alimentarius, Lact . sakei, Lact . curvatus and Lact . plantarum . SIGNIFICANCE AND IMPACT OF THE STUDY: In this paper, we have established the first species-specific primer for PCR identification of Lact . farciminis and Lact . alimentarius . Both species-specific primer and RFLP, could be used as tools for rapid identification of lactobacilli up to species level. J Appl Microbiol, 2003, 95(6), 1200 - 6 Screening and selection of exopolysaccharide-producing strains of Lactobacillus delbrueckii subsp . bulgaricus; Welman AD et al.; AIMS: The selection of exopolysaccharide (EPS)-producing strains of Lactobacillus delbrueckii subsp . bulgaricus . METHODS AND RESULTS: Improved EPS-overproducing strains of L . delbrueckii subsp . bulgaricus were derived by chemical mutagenesis and selection . Initial screening of the chemically induced mutant pool relied primarily on the selection of strains with raised levels of lactic acid and reduced biomass formation . Supporting selection criteria used were ropiness and colonial mucoidy . Final screening of candidate strains undertaken in a semi-defined medium in batch culture, resulted in the selection of a mutant with a 35% improvement in specific EPS yield relative to the parent strain . CONCLUSIONS: Initial selection of mutants of L . delbrueckii subsp . bulgaricus on the basis of enhanced formation of lactate and reduced biomass formation, coupled with a ropy or mucoid phenotype, proved to be a satisfactory means of isolating strains with the potential for a higher level of specific EPS production than the parent strain . SIGNIFICANCE AND IMPACT OF THE STUDY: The assay protocol allowed for the selection of an EPS-overproducing strain of L . delbrueckii subsp . bulgaricus . Such strains are useful for the purposes of metabolic studies related to EPS-production. Anal Chem, 2003 Sep 1, 75(17), 4423 - 31 pH-sensitive holographic sensors; Marshall AJ et al.; Holographic sensors for monitoring H+ (pH) have been fabricated from ionizable monomers incorporated into thin, polymeric, hydrogel films which were transformed into volume holograms using a diffusion method coupled with holographic recording, using a frequency doubled Nd:YAG laser (532 nm) . Unlike other optical pH sensors, it is possible to tailor the operational replay wavelength of the holographic sensor by careful control of the exposure conditions . The holographic diffraction wavelength (color) of the holograms was used to characterize their shrinkage and swelling behavior as a function of pH in various media . The effects of hydrogel composition, ionic strength, temperature, and factors influencing reversibility and response time are evaluated . Optimized holographic pH sensors show milli-pH resolution . The pH-sensing range of the holograms can be controlled through variation of the nature of the ionizable co-monomer used in polymer film construction; a series of holographic sensors displaying visually perceptible, fully reversible color changes over different pH ranges are demonstrated . A poly(hydroxyethyl methacrylate-co-methacrylic acid) holographic sensor was shown to be able to quantify the change in H+ concentrations in real time in a sample of milk undergoing homolactic fermentation in the presence of Lactobacillus casei. Can J Gastroenterol, 2003 Nov, 17(11), 655 - 9 Probiotic beverage containing Lactobacillus casei Shirota improves gastrointestinal symptoms in patients with chronic constipation; Koebnick C et al.; BACKGROUND: The aim of the present study was to investigate the effect of a probiotic beverage on gastrointestinal symptoms in patients with chronic constipation . METHODS: A double-blind, placebo-controlled, randomized study was conducted over a four-week period in patients with symptoms of chronic constipation (n=70) . To all patients, 65 mL/day of a probiotic beverage containing Lactobacillus casei Shirota (LcS) or a sensorially identical placebo was administered . Patients completed a questionnaire on gastrointestinal symptoms, well-being and stool habits and underwent a medical examination weekly . Severity of constipation, flatulence and bloating was summarized into four categories (severe, moderately severe, mild and no symptoms) . RESULTS: The consumption of LcS resulted in a significant improvement in self-reported severity of constipation and stool consistency, starting in the second week of the intervention phase (P<0.0001) . Severe and moderately severe constipation was observed less in the LcS group . The occurrence and degree of flatulence or bloating sensation did not change . In the final examination, 89% of the LcS group and 56% of the placebo group showed a positive effect of their beverage on constipation (P=0.003) . No adverse reactions were reported . CONCLUSIONS: The results indicate a beneficial effect on gastrointestinal symptoms of patients with chronic constipation . The administration of probiotic foodstuffs may be recommended as an adjunctive therapy of chronic constipation. Protein Eng, 2003 Nov, 16(11), 819 - 29 Homology modeling of the central catalytic domain of insertion sequence ISLC3 isolated from Lactobacillus casei ATCC 393; Lin TH et al.; The tertiary structure of the central catalytic domain of insertion sequence ISLC3 isolated from Lactobacillus casei ATCC 393 was predicted using the homology modeling approach . The novel insertion sequence was isolated by us from the template bacteriophage phiA3 of L.casei ATCC 393 . The number of amino acid residues of the ISLC3 central catalytic domain was 116 and was treated as the query sequence . There were five Web-available threading methods used to find some primary structure templates for the query sequence . These primary templates were further screened using the SWISS-MODEL Protein Modeling Server and the default parameter settings therein to give six final structure templates . All of these final structure templates were the integrase (IN) protein of retroviruses . Multiple sequence alignment using these IN sequences against the query one revealed the signature DDE motif . Based on the structures of these final templates, the structure of the query sequence was constructed using the InsightII/Discover/Homology programs . A metal ion, Mg(2+), was inserted into the center of the putative catalytic pocket formed by the DDE residues of the predicted structure in the final rounds of refinement by molecular dynamics (MD) simulations . The structure with a metal ion included was designated with Mg and that without a metal ion was designated free Mg . The average exposed surface area of some hydrophobic residues of both the predicted free Mg and with Mg structures were computed and compared with those computed for the six structure templates . Whereas the predicted with Mg structure was slightly more exposed than the predicted free Mg structure, the former appeared to be more stable than the latter, as revealed by the lower conformation energy recorded for the former during the structure refinement by MD simulations . To verify further the predicted structures, the coordinates of both predicted structures were fed into the ERRAT Protein Verification Server . It was found that the quality of the predicted with Mg structure was much better than that of the free Mg structure . The validation results also indicated that regions of the predicted with Mg structure that can be rejected at the 95% confidence level were approximately 20% whereas those which can be rejected at the same level for the six structure templates were approximately 10% . The predicted with Mg structure was also docked into a short oligonucleotide representing the substrate of the ISLC3 transposase using the DOCK_4.0.2 program . It was found that both Glu140 and Asp68 residues of the DDE motif of the predicted with Mg structure were able to form hydrogen bonds with the DNA substrate, which was similar to what was observed in a docking study using the retrovirus IN 1asu and its DNA substrate. J Food Prot, 2003 Nov, 66(11), 2038 - 44 Bactericidal effects of Lactobacillus reuteri and allyl isothiocyanate on Escherichia coli O157:H7 in refrigerated ground beef; Muthukumarasamy P et al.; Two naturally occurring antimicrobial agents were tested in packages of refrigerated ground beef for their ability to reduce the viability of Escherichia coli O157:H7 during storage . Allyl isothiocyanate (AITC) and Lactobacillus reuteri were tested separately and together for their action against a cocktail of five strains of E . coli O157:H7 in ground beef held at 4 degrees C for 25 days . Ground beef prepared from whole, raw inside round beef roasts was inoculated with low (3 log CFU/g) or high (6 log CFU/g) levels of the E . coli O157:H7 mixture . The beef was treated with AITC (about 1,300 ppm), L . reuteri, or both, along with 250 mM of glycerol per kg of meat at two levels (3 and 6 log CFU/g) and according to a design that yielded 8 controls plus 10 different treatments . Samples were analyzed for E . coli O157:H7 survivors, numbers of total bacteria, and lactic acid bacteria on days 0 to 25 at 5-day intervals . L . reuteri at both input levels with glycerol killed E . coli O157:H7 at both inoculated levels before day 20 . AITC completely eliminated E . coli O157:H7 at the low-inoculum level (3 log CFU/g) and reduced viability >4.5 log CFU/g at the high-inoculum level (6 log CFU/g) by the end of the storage period . The combination of L . reuteri and AITC did not yield an additive effect against E . coli O157:H7 viability . L . reuteri in the presence of glycerol was highly effective against E . coli O157:H7 in ground beef during refrigerated storage (4 degrees C) in modified atmosphere packages . Sensory testing is planned to evaluate effects of treatments. Scand J Rheumatol, 2003, 32(4), 211 - 5 Effects of probiotic therapy on the activity and activation of mild rheumatoid arthritis--a pilot study; Hatakka K et al.; OBJECTIVE: To study the effects of Lactobacillus rhamnosus GG (LGG) on rheumatoid arthritis (RA) . METHODS: Twenty-one RA patients were randomised to receive 2 capsules of LGG or a placebo twice daily in double-blind fashion for 12 months . Arthritis activity was evaluated by clinical examination, HAQ index, and laboratory tests (e.g . ESR, CRP, pro- and anti-inflammatory cytokines) . RESULTS: There were no statistical differences in the clinical parameters, biochemical variables and HAQ index between the study groups over the intervention period . The mean number of tender and swollen joints decreased from 8.3 to 4.6 in the Lactobacillus group and from 5.5 to 4.8 in the placebo group (p = 0.41) . According to the global assessment the RA activity was reduced in 71% (LGG group) vs . 30% (controls) (p = 0.15) . Serum IL-1 beta increased slightly in the LGG group (p = 0.07), but no differences were seen in IL-6, TNF-alpha, MPO, IL-10 or 1L-12 . CONCLUSIONS: Although there were no statistical significant differences in the activity of RA, more subjects in the LGG group reported subjective well being . More studies on the effects of probiotic bacteria in RA are needed. Biotechnol Appl Biochem . 2003 Nov 19; {Epub ahead of print} Modified alginate and chitosan for lactic acid bacteria immobilisation; Le-Tien C et al.; Beads with enhanced stability acid media based on alginate and chitosan functionalised by succinylation (increasing the anionic charges able to retain protons) or by acylation (improving the hydrophobicity of matrix) were developed for immobilisation of bacterial cells . Beads (3 mm diameter) formed by ionotropic gelation with CaCl 2 presented good mechanical characteristics . After 30 min incubation of viable free Lactobacillus rhamnosus cells in simulated gastric fluid (pH 1.5), an undetectable level of viable bacteria was noticed . Bacteria immobilisation in native alginate based beads generated a viable cells count of 22-26 %, whereas, when entrapped in succinylated alginate and chitosan beads, the percentage of viable cells was of 60 and 66 %, respectively . Best viability (87 %) was found for bacteria immobilised in N-palmitoylaminoethyl alginate, which affords a high protective effect probably due to long alkyl pendants that improve the beads hydrophobicity, limiting thus the hydration in the acid environment. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 281 - 6 Survival of Listeria monocytogenes on sliced cooked sausage after treatment with pediocin AcH; Mattila K et al.; A preparation with pediocin AcH bound to its heat-killed producer cells Lactobacillus plantarum WHE 92 (starter culture ALC01, Wisby, Denmark) by adjusting the pH of the preparation to 6.0 was studied for its effects against Listeria monocytogenes ATCC 7644 and (spoilage) lactic acid bacteria on sliced cooked sausage . The pediocin AcH preparation or 0.9% (w/w) NaCl dilution (as a control) were randomly distributed dropwise on the surface of the slices . Treated slices were vacuum-packed and stored at 6 degrees C . Microbiological analysis and determination of pH values were performed after 3, 6, 9, 14 and 21 days of storage . Flavour of the sausages was evaluated after 7 and 11 days of storage . The pediocin preparation had effect (p > 0.05) neither on the growth of lactic acid bacteria, on the pH value nor on the flavour of vacuum-packed sliced sausage during 21 days of storage compared to control . However, during 6 days of storage, the number of L . monocytogenes decreased from the initial level of 2.7 log cfu/g sausage to < 2 log cfu/g, while on the control sausages the number of L . monocytogenes remained at the inoculated level . The numbers of L . monocytogenes remained at those levels to the end of storage period (21 days) . However, the treated samples were determined to be Listeria positive, which indicates that the pediocin preparation was not efficient enough to kill all L . monocytogenes. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 265 - 73 Serine metabolism in Lactobacillus plantarum; Liu SQ et al.; This study investigated the metabolism of (L-) serine by Lactobacillus plantarum B3089 isolated from cheese . Serine was deaminated by growing cells to ammonia with the corresponding formation of acetate and formate . Serine was also deaminated by non-growing cells to ammonia but with the formation of acetate only (no production of formate) . Phosphoserine and threonine were not catabolised . It is proposed that serine was deaminated by serine dehydratase (deaminase) to ammonia and pyruvate . Pyruvate was further catabolised predominantly to acetate, carbon dioxide and formate in growing cells, catalysed by pyruvate-formate lyase and pyruvate oxidase; some of the pyruvate was converted to acetoin . In non-growing cells, however, pyruvate-formate lyase was inactive and pyruvate oxidase degraded the pyruvate to acetate and carbon dioxide . Serine dehydratase activity could not be detected in cell-free extracts, presumably because of enzyme instability . The growth of L . plantarum was neither enhanced nor stimulated by serine under the current conditions . Whereas there was little difference in serine utilisation between pH 7.0 and pH 5.8, serine utilisation was decreased by 30% at pH 5.0 . NaCl of up to 4% (w/v) concentration had little effect on serine utilisation . Serine had no impact on lactose metabolism . Lactose was fermented mainly to lactate (73%) with the remainder converted to an unidentified polysaccharide (27%). Int J Food Microbiol, 2003 Dec 31, 89(2-3), 205 - 12 Inhibition of Bacillus cereus by strains of Lactobacillus and Lactococcus in milk; Rossland E et al.; The growth and death or survival of Bacillus cereus in sterile skimmed milk fermented with 18 different lactic acid bacteria (LAB) were investigated . B . cereus alone in milk reached about 10(7)-10(8) colony-forming units (cfu)/ml . When B . cereus was cultivated together with different Lactobacillus or Lactococcus cultures at 30 or 37 degrees C, the B . cereus counts after 72 h of fermentation ranged between < 10 cfu/ml and about 10(6) cfu/ml . The inhibition patterns for the different Lactobacillus and Lactococcus cultures varied . All the Lactococcus cultures (with one exception) reduced pH to 5.3 or lower in 7 h . After 24 h, B . cereus was not detected in any of the fast Lactococcus-fermented milk samples . After 48 h, B . cereus was not detected for 4 of the 12 Lactobacillus cultures . These cultures reduced pH to below 5.0 in 24 h . The other Lactobacillus cultures also inhibited B . cereus, but the counts of B . cereus were still 10(4)-10(6) cfu/ml after 72 h . They also reduced pH at a slower rate . Survival of B . cereus was to a variable extent linked with formation of endospores . Proteinase K did not affect the antimicrobial activity observed . Acid production with decreasing pH, particularly the initial rate of pH decrease, appears to be most important for control of B . cereus with LAB. Int J Food Microbiol, 2003 Dec 31, 89(2-3), 105 - 24 Beer spoilage bacteria and hop resistance; Sakamoto K et al.; For brewing industry, beer spoilage bacteria have been problematic for centuries . They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Megasphaera cerevisiae . They can spoil beer by turbidity, acidity and the production of unfavorable smell such as diacetyl or hydrogen sulfide . For the microbiological control, many advanced biotechnological techniques such as immunoassay and polymerase chain reaction (PCR) have been applied in place of the conventional and time-consuming method of incubation on culture media . Subsequently, a method is needed to determine whether the detected bacterium is capable of growing in beer or not . In lactic acid bacteria, hop resistance is crucial for their ability to grow in beer . Hop compounds, mainly iso-alpha-acids in beer, have antibacterial activity against Gram-positive bacteria . They act as ionophores which dissipate the pH gradient across the cytoplasmic membrane and reduce the proton motive force (pmf) . Consequently, the pmf-dependent nutrient uptake is hampered, resulting in cell death . The hop-resistance mechanisms in lactic acid bacteria have been investigated . HorA was found to excrete hop compounds in an ATP-dependent manner from the cell membrane to outer medium . Additionally, increased proton pumping by the membrane bound H(+)-ATPase contributes to hop resistance . To energize such ATP-dependent transporters hop-resistant cells contain larger ATP pools than hop-sensitive cells . Furthermore, a pmf-dependent hop transporter was recently presented . Understanding the hop-resistance mechanisms has enabled the development of rapid methods to discriminate beer spoilage strains from nonspoilers . The horA-PCR method has been applied for bacterial control in breweries . Also, a discrimination method was developed based on ATP pool measurement in lactobacillus cells . However, some potential hop-resistant strains cannot grow in beer unless they have first been exposed to subinhibitory concentration of hop compounds . The beer spoilage ability of Pectinatus spp . and M . cerevisiae has been poorly studied . Since all the strains have been reported to be capable of beer spoiling, species identification is sufficient for the breweries . However, with the current trend of beer flavor (lower alcohol and bitterness), there is the potential risk that not yet reported bacteria will contribute to beer spoilage . Investigation of the beer spoilage ability of especially Gram-negative bacteria may be useful to reduce this risk. Oral Microbiol Immunol, 2003 Dec, 18(6), 389 - 92 Susceptibility of oral bacteria to Melaleuca alternifolia (tea tree) oil in vitro; Hammer KA et al.; The in vitro activity of Melaleuca alternifolia (tea tree) oil against 161 isolates of oral bacteria from 15 genera was determined . Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) ranged from 0.003 to 2.0% (v/v) . MIC90 values were 1.0% (v/v) for Actinomyces spp., Lactobacillus spp., Streptococcus mitis and Streptococcus sanguis, and 0.1% (v/v) for Prevotella spp . Isolates of Porphyromonas, Prevotella and Veillonella had the lowest MICs and MBCs, and isolates of Streptococcus, Fusobacterium and Lactobacillus had the highest . Time kill studies with Streptococcus mutans and Lactobacillus rhamnosus showed that treatment with > or = 0.5% tea tree oil caused decreases in viability of >3 log colony forming units/ml after only 30 s, and viable organisms were not detected after 5 min . These studies indicate that a range of oral bacteria are susceptible to tea tree oil, suggesting that tea tree oil may be of use in oral healthcare products and in the maintenance of oral hygiene. Arch Tierernahr, 2003 Oct, 57(5), 359 - 68 The effects of using lactic acid bacteria inoculants in maize silage on the formation of biogenic amines; Steidlova S et al.; Silages from five ripened varieties of silage maize with dry matter contents ranging between 275 and 410 g/kg were prepared in five laboratory experiments . Whole-plant maize was fermented at 22 degrees C and silages were then stored at the same temperature for 4 months . Spontaneously fermented silages were prepared as control variants and compared with silages inoculated with commercial strains of Lactobacillus plantarum, Lactobzcillus buchneri and a mixed preparation Microsil containing L . plantarum, Lactobacillus casei, Enterococcus faecium and Pediococcus pentosaceus . The starter cultures were applied at doses 5 x 10(5) and 5 x 10(6) CFU/g of chopped maize . Seven biogenic amines and polyamines were extracted from silages with perchloric acid and determined as N-benzamides by micellar electrokinetic capillary chromatography . Common chemical criteria of silage quality were also determined . All three inoculants, mainly at the higher dose, decreased significantly contents of tyramine, putrescine and cadaverine, three undesirable amines occurring at the highest levels . L . plantarum was the most effective . Contents of histamine and tryptamine were low in all experimental silages . Also relatively low were levels of polyamines spermidine and mainly of spermine. Mikrobiol Z, 2003 Jul-Aug, 65(4), 23 - 8 {Influence lactobacilli on the functional activity of macrophages and delayed hypersensitivity reaction in mice}; Ielyns'ka NO et al.; The influence of the genus Lactobacillus strains on the macrophages' functional activity and intensity of the delayed hypersensitivity reaction in mice has been studied . It has been shown that lactobacilli take positive effect on the cell-mediated mechanisms of the organisms' non-specific resistance and do not intensify the proceeding of specific immune reaction . The strain Lactobacillus fermentum ATCC 14931 is promising as the basis for the immunomodulatory probiotic preparation. J Ind Microbiol Biotechnol, 2003 Nov, 30(11), 661 - 8 Epub 2003 Nov 14. Fermentation performance of an exopolysaccharide-producing strain of Lactobacillus delbrueckii subsp . bulgaricus; Welman AD et al.; The formation of exopolysaccharide (EPS) and extracellular metabolites was studied in a strain of Lactobacillus delbrueckii subsp . bulgaricus (NCFB 2483), grown under batch culture conditions in a semi-defined medium incorporating lactose and casein hydrolysate . Performance parameters were derived from the fermentation data, and kinetic models were applied in order to describe the production of EPS, extracellular metabolites, and biomass produced . Lactose was split intracellularly, with the resultant galactose being exported from the cell, and the glucose being metabolised further to EPS and lactic acid . Production of EPS, lactate, and galactose was closely growth-associated and followed a pattern of primary kinetics . A marginally lower galactose level relative to the modelled levels throughout most of the time course of the fermentation suggests that not all galactose is exported from the cell, and that a low level of flux to other metabolites, such as EPS, might exist. J Bacteriol, 2003 Dec, 185(23), 6913 - 20 Structural analysis of the peptide pheromone receptor PlnB, a histidine protein kinase from Lactobacillus plantarum; Johnsborg O et al.; Intercellular communication plays a key role in the regulation of several physiological processes in gram-positive bacteria . Cell-cell communication is often mediated by secreted inducer peptide pheromones (IPs), which upon reaching a threshold concentration in the environment specifically activate a cognate membrane-localized histidine protein kinase (HPK) . Interestingly, the majority of IP-activated HPKs fall into one distinct subfamily (HPK(10)) . As part of an effort to study the mechanism underlying pheromone-mediated activation of the HPK(10) subfamily, the present work investigated the membrane topology of PlnB from Lactobacillus plantarum . Gene fusion experiments with Escherichia coli and Lactobacillus sakei, using alkaline phosphatase, beta-lactamase, and beta-galactosidase reporter fusions, suggested that PlnB is anchored to the cytoplasmic membrane via seven transmembrane segments . By domain switching between HPK(10) members, it was demonstrated that the determinants for pheromone binding and specificity are contained within the transmembrane domain . The results also indicate that the mechanism of signal transduction, in which the final transmembrane segment apparently plays a key role, is conserved between members of the HPK(10) subfamily. Am J Respir Crit Care Med, 2004 Feb 15, 169(4), 454 - 8 Epub 2003 Nov 14. Mouse lysozyme M is important in pulmonary host defense against Klebsiella pneumoniae infection; Markart P et al.; Klebsiella pneumoniae is a common virulent causative agent for pneumonia . Lysozyme has previously been shown to play an important role in nonimmune host defense of the airways . This study was undertaken to assess the role of lysozyme M, the major isoform of lysozyme in mouse lung, in the killing of K . pneumoniae in lysozyme M(-/-) mice and transgenic mice with increased expression of lysozyme (lysozyme(tg) mice) . The airways of lysozyme M(-/-) mice maintained in a pathogen-free facility were colonized by Lactobacilli, a component of the oropharyngeal flora . No lactobacilli were detected in the lungs of wild-type (WT) or lysozyme(tg) mice . Twenty-four hours after intratracheal infection with K . pneumoniae, bacterial killing was enhanced 9-fold in lysozyme(tg) mice compared with WT mice and 43-fold compared with lysozyme M(-/-) mice . In survival studies, no lysozyme M(-/-) mice survived beyond 72 hours after infection, whereas 75% of lysozyme(tg) (p < 0.01) and 25% of WT mice survived to 120 hours (p < 0.01) . Deficiency of lysozyme M in the lungs increased susceptibility to K . pneumoniae infection, whereas increased expression of lysozyme conferred resistance to infection and enhanced survival. J Med Microbiol, 2003 Dec, 52(Pt 12), 1117 - 24 Growth and lactic acid production by vaginal Lactobacillus acidophilus CRL 1259, and inhibition of uropathogenic Escherichia coli; Juarez Tomas MS et al.; Lactic acid-producing lactobacilli were selected from 134 human vaginal isolates by testing their capability to inhibit the growth of different pathogenic micro-organisms . Lactobacillus acidophilus CRL 1259 (from the CERELA Culture Collection) was selected to study the effects of temperature, pH and culture medium on growth and lactic acid production . Growth parameters were estimated by using the model of Gompertz . Kinetics of inhibition of uropathogenic Escherichia coli were evaluated in mixed cultures of the pathogen and L . acidophilus . Optimal conditions for growth and lactic acid production by L . acidophilus were pH 6.5 or 8.0 and 37 degrees C . Under these conditions, growth was higher in LAPTg (yeast extract/peptone/tryptone/Tween 80/glucose) broth than in MRS (De Man-Rogosa-Sharpe) broth . However, lactic acid production was more efficient in MRS broth . Under optimal conditions for lactic acid production, L . acidophilus inhibited the growth of E . coli . These results suggest that inclusion of L . acidophilus CRL 1259 in probiotic products for vaginal application would be beneficial. J Med Microbiol, 2003 Dec, 52(Pt 12), 1083 - 93 Susceptibility of oral bacteria to an antimicrobial decapeptide; Concannon SP et al.; Naturally occurring antimicrobial peptides have emerged as alternative classes of antimicrobials . In general, these antimicrobial peptides exhibit selectivity for prokaryotes and minimize the problems of engendering microbial resistance . As an alternative method to search for more effective broad-spectrum peptide antimicrobials, investigators have developed peptide libraries by using synthetic combinatorial technology . A novel decapeptide, KKVVFKVKFK (KSL), has been identified that shows a broad range of antibacterial activity . The purpose of this study was to test the efficacy of this antimicrobial peptide in killing selected strains of oral pathogens and resident saliva bacteria collected from human subjects . Cytotoxic activity of KSL against mammalian cells and the structural features of this decapeptide were also investigated, the latter by using two-dimensional NMR in aqueous and DMSO solutions . MICs of KSL for the majority of oral bacteria tested in vitro ranged from 3 to 100 microg ml(-1) . Minimal bactericidal concentrations of KSL were, in general, within one to two dilutions of the MICs . KSL exhibited an ED(99) (the dose at which 99 % killing was observed after 15 min at 37 degrees C) of 6.25 microg ml(-1) against selected strains of Lactobacillus salivarius, Streptococcus mutans, Streptococcus gordonii and Actinobacillus actinomycetemcomitans . In addition, KSL damaged bacterial cell membranes and caused 1.05 log units reduction of viability counts of saliva bacteria . In vitro toxicity studies showed that KSL, at concentrations up to 1 mg ml(-1), did not induce cell death or compromise the membrane integrity of human gingival fibroblasts . NMR studies suggest that KSL adopts an alpha-helical structure in DMSO solution, which mimics the polar aprotic membrane environment, whereas it remains unstructured in aqueous medium . This study shows that KSL may be a useful antimicrobial agent for inhibiting the growth of oral bacteria that are associated with caries development and early plaque formation. Appl Spectrosc, 2003 Feb, 57(2), 132 - 8 Near-infrared spectroscopy: a tool for monitoring submerged fermentation processes using an immersion optical-fiber probe; Tamburini E et al.; Near-infrared (NIR) spectroscopy has been developed as a noninvasive tool for the direct, real-time monitoring of glucose, lactic acid, acetic acid, and biomass in liquid cultures of microrganisms of the genera Lactobacillus and Staphylococcus . This was achieved employing a steam-sterilizable optical-fiber probe immersed in the culture (In-line Interactance System) . Second-derivative spectra obtained were subjected to partial least-squares (PLS) regression and the results were used to build predictive models for each analyte of interest . Multivariate regression was carried out on two different sets of spectra, namely whole broth minus the spectral subtraction of water, and raw spectra . A comparison of the two models showed that the first cannot be properly applied to real-time monitoring, so this work suggests calibration based on non-difference spectra, demonstrating it to be sufficiently reliable to allow the selective determination of the analytes with satisfactory levels of prediction (standard error of prediction (SEP) < 10%) . Direct interfacing of the NIR system to the bioreactor control system allowed the implementation of completely automated monitoring of different cultivation strategies (continuous, repeated batch) . The validity of the in-line analyses carried out was found to depend crucially on maintaining constant hydrodynamic conditions of the stirred cultures because both gas flow and stirring speed variations were found to markedly influence the spectral signal. Minerva Pediatr, 2003 Oct, 55(5), 447 - 52 {Prevention of antibiotic-associated diarrhea with Lactobacillus sporogens and fructo-oligosaccharides in children . A multicentric double-blind vs placebo study}; La Rosa M et al.; AIM: The aim of this paper is to determine the efficacy of a fructo-oligosaccharides (FOS)-Lactobacillus sporogenes preparation in the prevention of diarrhea due to antibiotics in childhood . METHODS: A multicentre, randomised, double-blind versus placebo study was carried out . A total of 120 children, with active infections requiring antibiotics, were enrolled in the study and treated for 10 days either in the experimental group (F) or in the placebo one (P) . The results of the study were recorded from the patients' diary and from follow-up clinical examinations . RESULTS: Out of 98 evaluable patients, 71% in group F had no diarrhea versus 38% in group P . The duration of diarrhea in F and P groups was 0.7 vs 1.6 days (p=0.002), respectively . CONCLUSION: Prophylaxis with Lactobacillus sporogens, associated to FOS, significantly reduced the number of days and duration of events in children with antibiotic-induced diarrhea. J Microbiol Methods, 2003 Dec, 55(3), 565 - 74 Construction and use of a computerized DNA fingerprint database for lactic acid bacteria from silage; Chan RK et al.; Efficient selection of new silage inoculant strains from a collection of over 10,000 isolates of lactic acid bacteria (LAB) requires excellent strain discrimination . Toward that end, we constructed a GelCompar II database of DNA fingerprint patterns of ethidium bromide-stained EcoRI fragments of total LAB DNA separated by conventional agarose gel electrophoresis . We found that the total DNA patterns were strain-specific; 56/60 American Type Culture Collection strains of 33 species of LAB could be distinguished . Enterococcus faecium strains ATCC19434 and ATCC35667 had identical total DNA patterns and RiboPrints . Lactobacillus rhamnosus strains ATCC7469 and ATCC27773 also had identical total DNA patterns, but different RiboPrints . EcoRI RiboPrint patterns could distinguish only about 9/23 Lactobacillus plantarum strains and about 6/10 Lactobacillus buchneri strains, whereas all 33 strains could be distinguished by EcoRI total DNA patterns . Despite gel-to-gel variation, new DNA patterns can be readily grouped with existing patterns using GelCompar II . The database contains large homogenous clusters of L . plantarum, E . faecium, L . buchneri, Lactobacillus brevis and Pediococcus species that can be used for tentative taxonomic assignment . We routinely use the DNA fingerprint database to identify and characterize new strains, eliminate duplicate isolates and for quality control of inoculant product strains . The GelCompar II database has been in continuous use for 7 years and contains more than 3600 patterns representing approximately 700 unique patterns from over 300 gels and is the largest computerized DNA fingerprint database for LAB yet reported. Scand J Infect Dis, 2003, 35(10), 759 - 62 How safe is safe?--a case of Lactobacillus paracasei ssp . paracasei endocarditis and discussion of the safety of lactic acid bacteria; Soleman N et al.; We report a case of endocarditis due to Lactobacillus paracasei ssp . paracasei, which could be distinguished from Lactobacillus strains used for the fermentation of dairy products by randomly amplified polymorphic DNA-polymerase chain reaction . The safety of biotechnical lactic acid bacteria use is also discussed. Vaccine, 2003 Dec 8, 22(1), 87 - 95 Mucosal co-application of lactic acid bacteria and allergen induces counter-regulatory immune responses in a murine model of birch pollen allergy; Repa A et al.; Recent epidemiological studies and clinical trials suggest a possible role of certain lactic acid bacteria (LAB) strains in the prevention of allergic diseases . In this study, we aimed at evaluating the immunomodulatory potential of two LAB strains, Lactococcus lactis and Lactobacillus plantarum, for prophylaxis and therapy of allergic immune responses . Both LAB strains-induced high levels of IL-12 and IFN-gamma in naive murine spleen cell cultures . Intranasal co-application with recombinant Bet v 1, the major birch pollen allergen, prior or after allergic sensitization, led to increased levels of allergen-specific IgG2a antibodies and in vitro IFN-gamma production, indicating a shift towards Th1 responses . Successful immunomodulation by the mucosal pre-treatment was further demonstrated by suppression of allergen-induced basophil degranulation . We conclude that these LAB strains in combination with an allergen could be promising candidates for mucosal vaccination against type I allergy. J Clin Pediatr Dent, 2003 Fall, 28(1), 13 - 7 Microbiology and management of endodontic infections in children; Brook I; The first step in the origination of caries is the formation of a dental plaque . Dental caries can lead to destruction of enamel and dentin resulting in bacterial invasion of the pulp . Invasion of the pulp and the periapical areas can promote the development of dento-alveolar abscess and spread of the infection to other anatomical areas . Several oral acid producing aerobic and anaerobic bacteria, including Streptococcus mutans, Lactobacillus acidophilus, and Actinomyces viscosus, are capable of initiating the carious lesion . The organisms that predominate in pulpitis and dento-alveolar abscess are Prevotella, Porphyromonas, Fusobacterium, and Peptostreptococcus spp . Treatment of caries involves removal of all affected tooth structure and proper replacement with a restorative material . Once pulpitis has developed the infected tissue should be removed and root canal therapy instituted, or the tooth should be extracted . Extraction, root canal therapy and/or drainage of pus usually are indicated for an abscess . Antimicrobial therapy supplementing the dental care should be considered, especially when local or systemic spread of the infection is suspected . Penicillin or amoxicillin are generally effective against most of the aerobic and anaerobic bacteria recovered . The patient whose oral cavity may harbor penicillin-resistant organisms should be considered for treatment with drugs effective against these organisms . These agents include amoxicillin-clavulanate, clindamycin or the combination of metronidazole plus amoxicillin or a macrolide. Appl Environ Microbiol, 2003 Nov, 69(11), 6816 - 24 Diversity and succession of the intestinal bacterial community of the maturing broiler chicken; Lu J et al.; The diversity of bacterial floras in the ilea and ceca of chickens that were fed a vegetarian corn-soy broiler diet devoid of feed additives was examined by analysis of 1,230 partial 16S rRNA gene sequences . Nearly 70% of sequences from the ileum were related to those of Lactobacillus, with the majority of the rest being related to Clostridiaceae (11%), Streptococcus (6.5%), and Enterococcus (6.5%) . In contrast, Clostridiaceae-related sequences (65%) were the most abundant group detected in the cecum, with the other most abundant sequences being related to Fusobacterium (14%), Lactobacillus (8%), and Bacteroides (5%) . Statistical analysis comparing the compositions of the different 16S rRNA libraries revealed that population succession occurred during some sampling periods . The significant differences among cecal libraries at 3 and 7 days of age, at 14 to 28 days of age, and at 49 days of age indicated that successions occurred from a transient community to one of increasing complexity as the birds aged . Similarly, the ileum had a stable bacterial community structure for birds at 7 to 21 days of age and between 21 to 28 days of age, but there was a very unique community structure at 3 and 49 days of age . It was also revealed that the composition of the ileal and cecal libraries did not significantly differ when the birds were 3 days old, and in fact during the first 14 days of age, the cecal microflora was a subset of the ileal microflora . After this time, the ileum and cecum had significantly different library compositions, suggesting that each region developed its own unique bacterial community as the bird matured. Appl Environ Microbiol, 2003 Nov, 69(11), 6750 - 7 Detection and identification of Lactobacillus species in crops of broilers of different ages by using PCR-denaturing gradient gel electrophoresis and amplified ribosomal DNA restriction analysis; Guan le L et al.; The microflora of the crop was investigated throughout the broiler production period (0 to 42 days) using PCR combined with denaturing gradient gel electrophoresis (PCR-DGGE) and selective bacteriological culture of lactobacilli followed by amplified ribosomal DNA restriction analysis (ARDRA) . The birds were raised under conditions similar to those used in commercial broiler production . Lactobacilli predominated and attained populations of 10(8) to 10(9) CFU per gram of crop contents . Many of the lactobacilli present in the crop (61.9% of isolates) belonged to species of the Lactobacillus acidophilus group and could not be differentiated by PCR-DGGE . A rapid and simple ARDRA method was developed to distinguish between the members of the L . acidophilus group . HaeIII-ARDRA was used for preliminary identification of isolates in the L . acidophilus group and to identify Lactobacillus reuteri and Lactobacillus salivarius . MseI-ARDRA generated unique patterns for all species of the L . acidophilus group, identifying Lactobacillus crispatus, Lactobacillus johnsonii, and Lactobacillus gallinarum among crop isolates . The results of our study provide comprehensive knowledge of the Lactobacillus microflora in the crops of birds of different ages using nucleic acid-based methods of detection and identification based on current taxonomic criteria. Plasmid, 2003 Nov, 50(3), 190 - 201 Sequence and genetic organization of the 19.3-kb erythromycin- and dalfopristin-resistance plasmid pLME300 from Lactobacillus fermentum ROT1; Gfeller KY et al.; Lactobacillus fermentum ROT1 was isolated from a raw milk dairy product . It is resistant to novobiocin, tetracycline, erythromycin and dalfopristin . A chromosomal tetracycline-resistance determinant was identified as tetM . A 19,398-bp plasmid (pLME300), present in several erythromycin-resistant strains of Lb . fermentum, was isolated from strain ROT1 and completely sequenced . Based on putative open reading frames, pLME300 contains at least four different functional regions . In region I, ORF1 shows high homologies to replication proteins of different theta-replicating plasmids . In addition, a tandem repeat of a 22-bp sequence appears 4.5 times . In region II, ORF3 may code for a methylase, and ORF4 has homologies to Mrr restriction system proteins of Deinococcus radiodurans and Escherichia coli suggesting a restriction-modification system . Region III harbours antibiotic-resistance genes, coding for a macrolide-lincosamide-streptogramin B (MLS) methylase Erm(LF) and the streptogramin A acetyltransferase Vat(E), which is identical to Vat(E) from Enterococcus faecium . Furthermore, region III shows a 91% nucleotide sequence identity to an erm-vat linkage of E . faecium . Region IV carries ORFs that appear to be involved in plasmid mobilization as characterized by a putative origin of transfer and a mobilization protein . pLME300 is the largest completely sequenced multi-resistance plasmid isolated from any Lactobacillus strain so far. J Dairy Sci, 2003 Oct, 86(10), 3048 - 53 Improvement of the resistance of Lactobacillus delbrueckii ssp . bulgaricus to freezing by natural selection; Monnet C et al.; Lactic acid bacteria are often produced as frozen or freeze-dried cultures that can be used for the direct inoculation of milk in cheese and fermented milk production processes . The objective of this study was to investigate whether the resistance of Lactobacillus delbrueckii ssp . bulgaricus to freezing could be improved by natural selection . Three parallel cultures of strain CFL1 were propagated for 30 cycles in which each cycle involved three serial transfers through milk, one freezing step, and one thawing step . The concentration in viable cells after thawing as well as the acidifying activity of the thawed cultures increased dramatically throughout the experiment . This may be explained by the random appearance of better-adapted mutants that can outcompete the other genotypes . However, after 30 cycles of subcultivation, freezing, and thawing, all the cultures contained subpopulations having different survival rates to freezing . Our results show that serial transfer culture experiments may be used to improve technological properties of lactic acid bacteria . Furthermore, investigation of the mutations that are responsible for an increased cryotolerance may help to define new targets for improving the resistance of lactic acid bacteria to several stresses. FEMS Microbiol Lett, 2003 Oct 24, 227(2), 271 - 7 PCR and RAPD identification of L . plantarum strains isolated from ovine milk and cheese . Geographical distribution of strains; Oneca M et al.; Lactobacilli, and specifically Lactobacillus plantarum, are an important group of microorganisms in ovine cheeses, even though they are not ordinarily included in the starter cultures added . The present study effected counts of lactobacilli in Roncal Protected Designation of Origin (PDO) milk and cheese samples and isolated a total of 1026 strains . The strains were identified to species level by polymerase chain reaction (PCR) using L . plantarum-specific oligonucleotide primers, and the strains belonging to this species were then characterized by randomly amplified polymorphic DNA (RAPD) . The percentage of L . plantarum present in the cheeses depended on the plant where the cheese was manufactured . Cluster analysis of the RAPD profiles obtained revealed seven main clusters . On comparing the strains, most of the strains present in the cheese were found not to have come from the raw milk. Am J Obstet Gynecol, 2003 Oct, 189(4), 1202 - 8 The potential for probiotics to prevent bacterial vaginosis and preterm labor; Reid G et al.; Infections of the urogenital tract in women represent a major burden on the quality of life of women and on the health care system of Canada and other countries . Complications arising from bacterial vaginosis (BV) include increased risk of sexually transmitted diseases including human immunodeficiency virus and elevated risk of preterm birth (PTB) . Pharmaceutical interventions, such as antibiotics, have been suboptimally effective and have failed to reduce the incidence of PTB . The absence of lactobacilli in the vagina, a specific feature of BV, raises the question as to whether restoration of lactobacilli, by probiotic therapy, can restore the normal flora and improve the chances of having a healthy term pregnancy . The rationale for probiotic use in pregnant women is quite strong . Certain lactobacilli strains can safely colonize the vagina after oral and vaginal administration, displace and kill pathogens including Gardnerella vaginalis and Escherichia coli, and modulate the immune response to interfere with the inflammatory cascade that leads to PTB . Additional attributes of probiotics include their potential to degrade lipids and enhance cytokine levels, which promote embryo development . In a society that focuses on disease rather than health and drug therapy rather than natural preventive measures, it will take some effort to get remedies such as probiotics into mainstream care . Perhaps the escalating health care budgets and emergence of "superbugs" will provide the incentives to put in place clinical trials designed to evaluate how best to use the commensal organisms that, after all, make up more of our body than human cells, and without which none of us would survive. Vaccine, 2003 Dec 1, 21(32), 4685 - 93 Reduced experimental autoimmune encephalomyelitis after intranasal and oral administration of recombinant lactobacilli expressing myelin antigens; Maassen CB et al.; Oral administration of autoantigens is a safe and convenient way to induce peripheral T-cell tolerance in autoimmune diseases like multiple sclerosis (MS) . To increase the efficacy of oral tolerance induction and obviate the need for large-scale purification of human myelin proteins, we use genetically modified lactobacilli expressing myelin antigens . A panel of recombinant lactobacilli was constructed producing myelin proteins and peptides, including human and guinea pig myelin basic protein (MBP) and proteolipid protein peptide 139-151 (PLP(139-151)) . In this study we examined whether these Lactobacillus recombinants are able to induce oral and intranasal tolerance in an animal model for multiple sclerosis, experimental autoimmune encephalomyelitis (EAE) . Lewis rats received soluble cell extracts of Lactobacillus transformants intranasally three times prior to induction of EAE . For the induction of oral tolerance, rats were fed live transformed lactobacilli for 20 days . Ten days after the first oral administration EAE was induced . Intranasal administration of extracts containing guinea pig MBP (gpMBP) or MBP(72-85) significantly inhibited EAE in Lewis rats . Extracts of control transformants did not reduce EAE . Live lactobacilli expressing guinea pig MBP(72-85) fused to the marker enzyme beta-glucuronidase (beta-gluc) were also able to significantly reduce disease when administered orally . In conclusion, these experiments provide proof of principle that lactobacilli expressing myelin antigens reduce EAE after mucosal (intranasal and oral) administration . This novel method of mucosal tolerance induction by mucosal administration of recombinant lactobacilli expressing relevant autoantigens could find applications in autoimmune disease in general, such as multiple sclerosis, rheumatoid arthritis and uveitis. Minerva Ginecol, 2003 Jun, 55(3), 279 - 84, 284-7 Adherence of Lactobacillus plantarum P 17630 in soft-gel capsule formulation versus Döderlein's bacillus in tablet formulation to vaginal epithelial cells; Bonetti A et al.; BACKGROUND: To evaluate in vitro the adherence capability of two bacteria to vaginal epithelial cells (VEC) by comparing product A containing L . plantarum P 17630, in soft-gel capsule formulation* and product B containing Doderlein's bacillus, now classified as L . gasseri, in vaginal tablet formulation, marketed for many years in Italy . METHODS: The comparative study of two commercially available preparations followed an open, controlled trial . Collection of VEC samples was done in an ambulatory setting; the adherence tests were carried out at the Institute of Microbiology of the Universita Cattolica del Sacro Cuore, Piacenza . The study was made on intact VEC, washed and drawn from 20 patients affected by bacterial vaginitis and/or vaginosis . One capsule or tablet, suspended in physiological solution, was mixed with a suspension of VEC . Adherence of lactobacilli to the VEC was counted by light microscopy and by CFU cultured on the plates . The type of adhesion was evaluated as well . RESULTS: The mean number of lactobacilli adhering to individual VEC was higher for product A containing L . plantarum P 17630 . On the plate cultures, 10(6)-10(8) CFU/sample were found for product A, compared with 10(2)-10(4) CFU/sample for product B . L . plantarum P-17630 adhere prevalently to single cells, whereas L . gasseri adhere by forming small chains . CONCLUSIONS: Product A has a better capability of adherence to VEC than does product B . Even the type of adhesion of L . plantarum P 17630 enabled it to remain better attached to the VEC . The results suggest that in vivo product A may be more likely to provide better colonization, thus affording better protection of the vaginal milieu. Int J Food Microbiol, 2003 Dec 15, 89(1), 67 - 75 Growth of Lactobacillus paracasei ssp . paracasei on tofu whey; Le NT et al.; The liquid by-product of the soybean product tofu, tofu whey (TW), was used as a growth medium for the production of Lactobacillus paracasei ssp . paracasei LG3 cultures . The TW used in this study contained stachyose, raffinose, sucrose, fructose and glucose, but the strain used could only utilize the three latter . The lactobacilli population obtained in MRS broth was three times higher than that in TW alone, and supplementation of TW was thus examined . Of 19 mixtures of yeast extracts (YE), peptones and potato extracts examined, the best nitrogen sources were YE and tryptone . The addition of YE, salts (phosphates, citrates, Mg and Mn), glucose as well as Tween to TW tripled the populations to 2.9 x 10(9) cfu/ml, which was as high as that obtained in MRS broth . Growth of L . paracasei LG3 in cow rehydrated skim milk was inferior to that in TW. Int J Food Microbiol, 2003 Dec 15, 89(1), 41 - 50 Antimicrobial interactions of microbial species involved in the fermentation of cassava dough into agbelima with particular reference to the inhibitory effect of lactic acid bacteria on enteric pathogens; Mante ES et al.; Lactic acid bacteria, Bacillus species and yeasts are involved in the fermentation of cassava dough into agbelima . Microbial interactions within and between these groups of microorganisms were investigated in addition to the survival of five enteric pathogens inoculated into agbelima under various conditions . Nine out of 10 cultures of lactic acid bacteria isolated at the end of agbelima fermentation showed inhibitory effect against 10 cultures of lactic acid bacteria isolated at the start of fermentation . Only 3 out of 10 isolates of Bacillus subtilis were inhibited by 10 isolates of lactic acid bacteria tested . No interactions were observed between yeasts and the lactic acid bacteria, whereas three of the Bacillus isolates showed inhibitory effects against the yeasts . Twelve isolates of Lactobacillus plantarum tested inhibited the growth of an isolate each of Lactobacillus fermentum and Lactobacillus brevis but none tested positive for bacteriocin production . The antimicrobial effect of the lactic acid bacteria was attributed to acid production . In fermenting cassava dough, enteric pathogens survived to different extents depending on pH and their sensitivity to acids . Vibrio cholerae C-230, Salmonella typhimurium 9 and Salmonella enteritidis 226 were not detectable in 10 g of sample after 4 h when inoculated into the 48-h fermented product, agbelima, whereas Shigella dysenteriae 2357T and Escherichia coli D2188 were detectable up to 8 h in the product. Int J Food Microbiol, 2003 Dec 15, 89(1), 21 - 9 Use of redox potential modification by gas improves microbial quality, color retention, and ascorbic acid stability of pasteurized orange juice; Alwazeer D et al.; The aim of this paper was to study the effect of both redox potential (Eh) and pasteurization of orange juice on stability of color and ascorbic acid, and growth recovery of microorganisms during storage at 15 degrees C for 7 weeks . Three conditions of Eh, +360 mV (ungassed), +240 mV (gassed with N2), and -180 mV (gassed with N2-H2) were applied to orange juice . Both thermal destruction and recovery of sublethall