Scand J Dent Res, 1979 Apr, 87(2), 129 - 39 A comparison between different methods for prediction of caries activity; Klock B et al.; The aim of the study was to find out if any of the following factors, alone or in combination, could be used for prediction of caries activity: salivary S . mutans, salivary lactobacilli, buffer capacity, saliva secretion rate, salivary pH, the amount of plaque and the caries frequency . The patient material consisted of 300 children between 9 and 12 years old . The increment of caries after 1 and 2 years was compared with all the above factors registered at baseline . Only the factors caries frequency and S . mutans showed a significant correlation to caries activity . In one of the tests the lactobacillus count approached significance . The combination of high numbers of incipient smooth surface lesions, S . mutans and lactobacilli gave a mean value of caries activity almost three times that of the whole group (8.4 versus 3.1). J Pharm Sci, 1979 Apr, 68(4), 496 - 9 Effect of N-trifluoroacetyl derivatives of amino acids and amino acid analogs on microbial antitumor screen; Otani TT et al.; Eighteen trifluoroacetyl derivatives of amino acids and of amino acid analogs were prepared and tested for growth-inhibitory activity using a Lactobacillus casei system as a prescreen for antitumor activity . Of the compounds tested, the trifluoroacetyl derivatives of o-, m-, and p-fluorophenylalanine and of beta-3-thienylalanine showed modest activity; trifluoroacetyl derivatives of phenylalanine and of beta-2-thienylalanine showed marginal activity . The activity exhibited by the active trifluoroacetyl compounds was equal to that noted for most active chloroacetyl derivatives reported previously, as judged by comparison of their activity with that of chloroacetyl-m-fluorophenylalanine . No reversal of inhibition was noted when a representative of these inhibitors was challenged with a corresponding natural metabolite, both as a free amino acid and as a noninhibitory acylated compound. Scand J Haematol, 1979 Mar, 22(3), 241 - 5 Serum erythrocyte folate levels in thalassaemic patients in Thailand; Vatanavicharn S et al.; The mean serum and adjusted red cell folate levels, as measured by microassay using Lactobacillus casei, respectively were 8.87 +/- SD 3.28 microgram/l and 436 +/- SD 107 microgram/l in 76 normal subjects, 4.22 +/- SD 2.70 microgram/l and 182 +/- SD 114 microgram/l in 55 patients with beta-thalassaemia/Hb E disease and 6.36 +/- SD 2.95 microgram/l and 320 +/- 158 microgram/l in 37 patients with Hb H disease . The mean serum and adjusted red cell folate values of the patients with beta-thalassaemia/Hb E disease and the mean serum folate value of the patients with Hb H disease were significantly lower than those of the normal subjects (P less than 0.001) . 33% of the beta-thalassaemia/Hb E patients and 8% of the Hb H patients showed low serum folate levels (less than 3 microgram/l) whereas 84% of the former and 45% of the latter showed low adjusted red cell folate levels (less than 270 microgram/l) . The group of beta-thalassaemia/Hb E disease with low serum folate levels had lower mean haemoglobin concentration and lower mean adjusted red cell folate level than the group with normal serum folate levels . Since the Thai diets have high folate content, the observed low serum and erythrocyte folate levels in thalassaemic patients most likely occur from massively increased erythropoiesis . Folate, 5 mg/d, is now routinely prescribed to such patients especially to those with severe anaemia. J Biol Chem, 1979 Feb 25, 254(4), 1296 - 300 The primary structure of Lactobacillus casei thymidylate synthetase . II . The complete amino acid sequence of the active site peptide, CNBr 4; Bellisario RL et al.; The 102 amino acid residues of CNBr 4, the largest of 5 cyanogen bromide peptides from the Lactobacillus casei thymidylate synthetase were completely sequenced by means of limited tryptic, tryptic, chymotryptic, and staphylococcal protease peptides . CNBr 4 contains both of the cysteines in an enzyme subunit, with the 5-fluorodeoxyuridylate-reactive cysteine at residue 198 and the other at residue 244. J Biol Chem, 1979 Feb 25, 254(4), 1288 - 95 The primary structure of Lactobacillus casei thymidylate synthetase . I . The isolation of cyanogen bromide peptides 1 through 5 and the complete amino acid sequence of CNBr 1, 2, 3, and 5; Maley GF et al.; Thymidylate synthetase from Lactobacillus casei was S-carboxymethylated and degraded by treatment with cyanogen bromide . Although the protein contains 6 methionine residues, only 5 cyanogen bromide peptides were obtained due to the presence of 1 methionine on the NH2 terminus and another adjacent to a threonine residue which was resistant to cleavage . The peptides were isolated by differential extraction, first with ammonium acetate, then pyridine acetate, and finally the residue was solubilized with 50% acetic acid . Each peptide was further purified to homogeneity by Bio-Gel chromatography . The size of the peptides from the amino to carboxyl end of the enzyme subunit was CNBr 1, 4,100; CNBr 2, 10,300; CNBr 3, 8,100; CNBr 4, 11,800; CNBr 5, 2,200 . The sum of the amino acid residues of the peptides is equal to the sum of the residues in an enzyme subunit, indicating that all of the CNBr peptides have been isolated . The CNBr-resistant methionine was located in CNBr 2 and the 5-fluoro-2'-deoxyuridine 5'-monophosphate binding site in CNBr 4 . The holoenzyme molecular weight, based on the residue weights of the amino acids in the two equivalent subunits, is equal to 73,176 . The complete sequence of each of the CNBr peptides, except for CNBr 4, which is presented in the following paper, is described. Biochem J, 1979 Feb 1, 177(2), 425 - 32 Circular-dichroism studies of ligand binding to dihydrofolate reductase from Lactobacillus casei MTX/R; Hood K et al.; Circular-dichroism spectra (200--450 nm) were recorded for Lactobacillus casei MTX/R dihydrofolate reductase and its complexes with substrates, inhibitors and coenzymes . These spectra are compared with those reported by others for dihydrofolate reductase from other sources . The binding of NADP+ or NADPH is associated with the perturbation of one or more aromatic amino acid residues, and there is marked enhancement of the negative c.d . band at 340 nm arising from the dihydronicotinamide chromophore of NADPH . The substrates folate and dihydrofolate give rise to substantial extrinsic c.d . bands on binding, which show a number of specific differences between enzymes from different sources . The binary complexes between the enzyme and the inhibitors methotrexate or trimethoprim also show strong c.d . bands, and these are qualitatively very similar for all dihydrofolate reductases studied so far . The ternary complexes between enzyme, NADPH and trimethoprim or methotrexate are very different from the sum of the spectra of the binary complexes . Trimethoprim leads to the disappearance of the 340 nm c.d . band of bound NADPH, whereas in the methotrexate--NADPH--enzyme ternary complex a "couplet" c.d . spectrum is observed at long wavelengths . Analysis of this latter feature suggests that it arises from a direct interaction between the dihydronicotinamide and pteridine rings in the ternary complex. Proc Natl Acad Sci U S A, 1979 Feb, 76(2), 750 - 4 Thymidylate synthetase purified to homogeneity from human leukemic cells; Lockshin A et al.; Thymidylate synthetase (5,10-methylenetetrahydrofolate:dUMP C-methyltransferase, EC 2.1.1.45) from a human leukemic cell line has been purified to homogeneity with one-step affinity column chromatography . The purified enzyme has a specific activity of 3.8 micron/min per mg of protein, which corresponds to a turnover number of 250 . These are the highest values reported for a thymidylate synthetase from neoplastic tissue . A ratio of 1.7 mol of 5-fluoro-2'-deoxyuridylate binds per mol of enzyme in the presence of 5,10-methylenetetrahydrofolate . The ternary complex so formed migrates intact on denaturing gels and can be precipitated with trichloroacetic acid; however, urea dissociates the ternary complex . The human thymidylate synthetase is composed of two subunits of 33,000 daltons each . It contains more residues of cysteine, glycine, and arginine and fewer of histidine than the well-studied thymidylate synthetase from Lactobacillus casei. J Biol Chem, 1979 Jan 25, 254(2), 480 - 8 The amino acid sequence of dihydrofolate reductase from the mouse lymphoma L1210; Stone D et al.; The determination of the amino acid sequence of the dihydrofolate reductase (EC 1.5.1.3) from cells of the mouse lymphoma L1210 is described . The protein was cleaved by cyanogen bromide to produce the six fragments CB1 (residues 1 to 14), CB2 (residues 15 to 52), CB3 (residues 53 to 111), CB4 (residues 115 to 125), CB5 (residues 126 to 139), and CB6 (residues 140 to 186) . One of the fragments, CB2, contained an internal homoserine derived from a methionine which was not cleaved by cyanogen bromide . The amino acid sequences and order of the cyanogen bromide fragments were determined by a combination of automatic and manual sequence analyses of the fragments and small peptides from tryptic, thermolytic, and Staphylococcus aureus protease digestions . The complete sequence comprises 186 residues in a single polypeptide chain of molecular weight 21,458 . Comparison of the sequence of the L1210 dihydrofolate reductase with the sequences of the enzymes from Streptococcus faecium, escherichia coli RT500, and Lactobacillus casei indicates that all enzymes show some homology, which is strongest in the regions forming the substrate binding cleft. Am J Obstet Gynecol, 1979 Jan 15, 133(2), 139 - 44 Quantitative bacteriology of the vaginal flora in vaginitis; Levison ME et al.; Vaginal flora was studied quantitatively in 29 sexually active women, 16 to 33 years of age, to define the role of C . vaginale in vaginitis . Seventeen were asymptomatic and 12 complained of symptoms of vaginitis . Seven asymptomatic women had scant secretions: four of these seven had C . vaginale at log10 6 to 9 CFU per milliliter, none of whom had "clue" cells; none had trichomonas or candida; six had lactobacilli at log10 7 to 9.7 per milliliter; only one had Bacteroidaceae at greater than log10 5 per milliliter . Ten asymptomatic women had easily collectable secretions; eight of 10 had C . vaginale at log10 6.5 to 9.6 per milliliter, three of whom had "clue" cells; four had trichomonas and none candida; nine had Lactobacilli at log10 7 to 9.3 per milliliter; four had Bacteroidaceae at greater than log10 5 per milliliter . Twelve had vaginitis: five of 12 had C . vaginale at log10 7.9 to 11 per milliliter, one of whom had "clue" cells; nine had either trichomonas or candida or both and three had no pathogen, including C . vaginale; 10 had Lactobacilli at log10 7 to 10 per milliliter; six had Bacteriodaceae at greater than log10 5 per milliliter . Three had "clue" cells in absence of C . vaginale. Clin Chem, 1979 Jan, 25(1), 108 - 10 Radioimmunoassay for pantothenic acid in blood and other tissues; Wyse BW et al.; We describe a radioimmunoassay for pantothenic acid in biological tissues . D-Pantothenic acid was conjugated with bovine serum albumin by use of a bromoacetyl derivative of pantothenic acid, and antibody to this antigen was raised by injecting it into the foot pads of rabbits . For the radioimmunoassay, a 100-fold dilution of the resulting antiserum was incubated with radiolabeled pantothentic acid . The antibodies were precipitated and dissolved, and the radioactivity of the solution was measured in a liquid scintillation counter . Between 5 and 125 ng of pantothenic acid can be detected in 75 muL of tissue extract . Validation included recovery and precision studies, parallelism with tissue extracts, and competitive binding studies . Results of the radioimmunoassay and those of microbiological assay with use of Lactobacillus plantarum correlated well (r = 0.80). Am J Clin Nutr, 1979 Jan, 32(1), 92 - 5 Folate conjugase activity in fresh vegetables and its effect on the determination of free folate content; Leichter J et al.; The levels of naturally-occurring folate conjugates in fresh asparagus, broccoli, Brussels sprouts, cabbage, cauliflower lettuce, and spinach were determined together with the effect on the hydrolysis of pteroylpolyglutamates during the extraction phase of the Lactobacillus casei assay . The levels of conjugate activity vary widely among the vegetables tested, from a low of 0.30 +/- 0.21 in lettuce to a high of 106.2 +/- 6.6 mumoles/hr per 100 mg of fresh weight in spinach . The free folate values (L . casei activity before chicken pancreas conjugase treatment) in the fresh vegetables boiled 1 hr after homogenization were significantly higher than those in vegetables boiled before homogenization, while there were no significant differences in total folate (L . casei activity after treatment with conjugase from chicken pancreas) . The increase in free folate values must have been due to the action of endogenous conjugases on the pteroylpolyglutamates from the time the vegetables were homogenized until the conjugase was inactivated by heat . It is concluded that reliable free folate values in fresh vegetables can be obtained only if the naturally present conjugases are inactivated before homogenization of sample in order to prevent the hydrolysis of the pteroylpolyglutamates in the vegetables. Zentralbl Bakteriol Naturwiss, 1979, 134(6), 544 - 6 Lactic acid production from molasses by mixed population of lactobacilli; Tiwari KP et al.; The production of lactic acid from molasses by mixed populations of (1) Lactobacillus bulgaricus AU (isolated from curd) and L . casei (supplied by NCL, Poona-8, India) and (2) L . bulgaricus, L . delbrueckii (supplied by NCL, Poona-8, India), and L . casei was studied . It has been found that association of L . bulgaricus with L . casei slightly enhances the yield of lactic acid, while the mixed population of L . bulgaricus, L . delbrueckii, and L . casei is as effective as L . bulgaricus alone. Zentralbl Bakteriol Naturwiss, 1979, 134(8), 748 - 50 The influence of mutagenic chemicals on lactic acid fermentation by Lactobacillus bulgaricus AU; Tiwari KP et al.; Lactic acid fermentation from molasses by L . bulgaricus AU in the presence of caffeine and ammonium fluoride was studied . It was found that caffeine had a stimulating effect only at lower concentration (0.001%-0.002%), while at high concentration the acid-producing activity of the bacteria was considerably depressed . Ammonium fluoride, at a concentration of 0.001%-0.005%, had a stimulating effect on the activity of the bacteria, maximum activity was observed at a concentration of 0.003%. Ultramicroscopy, 1979, 3(3), 337 - 42 Electron diffraction studies of the peptidoglycan of bacterial cell walls; Formanek H et al.; Peptidoglycan of the gram-positive bacterium Lactobacillus plantarum was adsorbed onto hydrophilic crystalline films of graphitic oxide . Destruction by radiation damage was reduced by using a device which permitted scanning of the specimen for several hours through a focussed electron beam of low current density (2.5 X 10(-5) A/cm2) . In additition to the sharp Debye-Scherrer rings caused by graphitic oxide, peptidoglycan causes a diffuse Debye-Scherrer ring in the region of 4.5 A . This can be interpreted as the packing periodicity of the peptidoglycan within the planes of the peptidoglycan sacculi. Chemotherapy, 1979, 25(4), 243 - 8 Reaction of the vaginal flora to ornidazol in patients with cervicitis; Lindner JG et al.; The cervical and high vaginal flora of 76 patients with cervicitis were studied before and after therapy with Ornidazol by quantitative culture methods . Lactobacilli were the predominant organisms, but Peptostreptococci, Bacteroides and Trichomonas were encountered in 17, respectively 32 and 81% of all specimens . During and after therapy Trichomonas disappeared completely, the bacterial flora normalized and became comparable to that of healthy women with incidences for Bacteroides of 8-13% and Peptostreptococci of 4-5% . The in vitro susceptibility (MIC and MBC) of 50 strains of Bacteroides to Ornidazol was determined by a broth dilution method and an agar plate technique . The MIC varied from 0.07 to 10 microgram/ml . All strains were susceptible to 10 microgram/ml . There was a slight variation in resistance between the various species tested . B . fragilis was less susceptible to Ornidazol than other Bacteroides species . Within the species B . fragilis the subspecies thetaiotaomicron and 'other' were most susceptible, spp . fragilis and spp . distasonis least. J Clin Microbiol, 1979 Jan, 9(1), 33 - 7 Characterization of a Haemophilus paracuniculus isolated from gastrointestinal tracts of rabbits with mucoid enteritis; Targowski S et al.; The isolation, characterization, and identification of a microorganism isolated from gastrointestinal tracts of rabbits with mucoid enteritis are described . The isolated organism did not grow on standard media . This organism grew around colonies of Staphylococcus aureus and Lactobacillus desidiosus and around disks saturated with diphosphopyridin nucleotide (factor V) on brain heart infusion agar . The growth of this organism was also observed on media supplemented with beta-nicotinamide adenine dinucleotide . The organism appeared as gram-negative, pleomorphic rods or coccobacilli . It was positive for urease, oxidase, catalase, glycosidases, porphyrin, and indole, and it fermented glucose and sucrose . All of these characteristics suggest that the organism is a member of the genus Haemophilus . Because of its isolation from rabbits and differences in some characteristics from other species of this genus, the name Haemophilus paracuniculus is proposed for this organism. Nutr Metab, 1979, 23(3), 227 - 34 Identification of antimicrobial alpha-hydroxyacids in Lactobacillus plantarum-fermented animal protein; Hietala PK et al.; During the fermentation of animal protein by Lactobacillus plantarum, highly volatile and less volatile antimicrobial substances are formed . The antimicrobial effect of the latter fraction depends on the content of alpha-hydroxyacids in the fermentation product . These acids were isolated from the fermentation mixture and identified by chemical methods . The main components are racemic forms of lactic, alpha-hydroxyisovaleric and alpha-hydroxyisocaproic acids. Dtsch Zahnarztl Z, 1979 Jan, 34(1), 13 - 5 {The effect of sorbide on the amount of lactobacillus in the saliva}; Banoczy J et al.; Saliva specimens from school children in the children's village of Fot were cultured in dentocult medium and the lactobacilli were counted . In addition to their usual food, the children also consumed 20 g of chocolate with either 40% sucrose or sorbitol . The control group was composed of children living in Budapest . High lactobacillus counts were observed less frequently in the sorbitol group than in the other groups . There was a positive correlation between the number of lactobacilli in the saliva and the intensity of caries. Cancer Biochem Biophys, 1979, 3(2), 57 - 64 Denaturation of thymidylate synthetase from amethopterin-resistant Lactobacillus casei; Reinsch JW et al.; The effects of various concentrations of urea and guanidine hydrochloride on enzyme activity and on subunit association were determined . Incubation of thymidylate synthetase with buffered solutions of 3M to 3.5M guanidine hydrochloride or 5 M to 6 M urea resulted in the loss of about 90% of the enzyme activity . Under these denaturing conditions a red shift of the fluorescence emission maximum from 340 nm to 351 nm was observed together with a significant decrease in the relative fluorescence intensity of the protein . Studies at both 4 degrees C and 25 degrees C indicated that the enzyme was in the dimer form in 2 M guanidine hydrochloride but was dissociated into monomers in concentrations of this denaturant of 3 M and above . Although only monomeric species were evident at 4 degrees C in 6 M urea, at 25 25 degrees C this denaturant caused protein aggregation which increased with decreasing phosphate buffer concentration . Enzyme (5 mg/ml) in 0.5 M potassium phosphate buffer, pH 6.8, containing 4 M guanidine hydrochloride gave a minimum S20, w value of 1.22S at 25 degrees C . Sedimentation behavior of the native enzyme in the range of 5 to 20 mg/ml was only slightly concentration-dependent (4.28 S to 4.86 S) but extensive aggregation occurred above 20 mg/ml. J Nutr Sci Vitaminol (Tokyo), 1979, 25(5), 361 - 6 Vitamin B2 activity of 7,8-dimethyl-10-(2,3,4-trihydroxy-4-formylbutyl)isoalloxazine in Lactobacillus casei; Tachibana S et al.; The microbial activities of vitamin B2-aldehyde and vitamin B2-acid, produced by Schizophyllum commune, a Basidiomycete, were studied . Lactobacillus casei ATCC No . 7469 was used as a test microorganism . B2-aldehyde exhibited a good response curve in the growth of L . casei . B2-acid had neither a stimulatory nor an inhibitory effect on the growth . When B2-aldehyde was incubated with the homogenate of L . casei, it was converted to riboflavin . The flavin formed from B2-aldehyde by the homogenate not only exhibited an equivalent response curve to authentic riboflavin in the growth of L . casei, but also showed the same Rf value as authentic riboflavin in any paper chromatogram, as far as tested . Hence, the microbial activity of B2-aldehyde for L . casei seems to be ascribable to riboflavin which is a reduction product of B2-aldehyde. Pathology, 1979 Jan, 11(1), 45 - 52 Interpretation of serum and red cell folate results . A comparison of microbiological and radioisotopic methods; Jones P et al.; Serum folate and red blood cell folate levels were measured in 167 patients using a microbiological method (Lactobacillus casei) and a commercial 125I radioassay kit . The results of the two methods were compared and related to the clinical findings to see which method more truly reflected the physiological folate status of the patient . There was a good linear correlation between the methods for both serum folate and red cell folate over the whole range encountered and the mean results obtained with each method were nearly identical . Both methods seemed to perform equally well in distinguishing low serum folate levels, but when the red cell folate results were compared to the clinical and other laboratory findings, the radioassay more closely related to the folate status of the patient . The study again emphasized the high number of low serum folate levels found in hospital patients and the importance of measuring the red cell folate. Clin Exp Immunol, 1979 Jan, 35(1), 128 - 32 Bacterial and strain specificities in opsonization, phagocytosis and killing of Streptococcus mutans; Scully CM et al.; Opsonization of Streptococcus mutans, followed by phagocytosis and killing by polymorphonuclear leucocytes has been postulated as an effector mechanism in protection against dental caries . Opsonization was studied by using sera from monkeys immunized with killed Strep . mutans (sero-type c) and compared with sera from sham-immunized monkeys . Antibodies to Strep . mutans (sero-type c) induced maximal phagocytosis and killing of serotypes c and e, and this was significantly greater than with serotypes a and d; there was no significant phagocytosis or killing of serotype b . There was little or no opsonization with Actinomyces viscosus, Lactobacillus casei, Strep, sanguis and Strep . salivarius . The exception was Strep . CHT which showed significant phagocytosis and killing . The results suggest that immunization with the serotype c strain of Strep . mutans might offer protection against four of the five common serotypes of this organism. J Bacteriol, 1979 Jan, 137(1), 614 - 9 Transfer of plasmid-mediated antibiotic resistance from streptococci to lactobacilli; Gibson EM et al.; The transmissible plasmid pAMbeta1, which codes for erythromycin and lincomycin resistance, was conjugally transferred from a Lancefield group F Streptococcus to a strain of Streptococcus avium . Both organisms served as pAMbeta1 donors for three strains of Lactobacillus casei . Introduction of pAMbeta1 into one of the L . casei strains caused the organism to lose its native 6.7 X 10(6)-dalton plasmid . Loss of the native plasmid produced no alterations in the organism's growth characteristics or fermentation pattern. J Gen Virol, 1979 Jan, 42(1), 27 - 36 Adenosine triphosphate content in Lactobacillus casei and the blender-resistant phage-cell complex-forming ability of cells on infection with PL-1 phage; Watanabe K et al.; The intracellular ATP content of Lactobacillus casei ATCC 27092 grown in a glucose-containing medium was almost constant (2 to 3 microgram/mg dry wt . cells) through the early to middle stage of logarithmic phase, but it was lowered to less than 0.1 microgram/mg after cessation of growth owing to the exhaustion of available glucose . All the cells in the early stage of stationary phase were still viable and thus considered to be in a starved state . When such starved cells were infected with PL-1 phages in a tris-maleate buffer of pH 6.0, the process of forming blender-resistant phage-cell complexes signifying the complete injection of phage genomes into the cells was much inhibited . There was a good correlation between the ATP content of cells and the extent of the formation of blender-resistant phage-cell complexes and the correlation coefficient between them was 0.89 + 0.09 at the 95% confidence limit . On the other hand, the process of forming both the phage-adsorbed cells and the anti-phage serum-resistant phage-cell complexes were not affected by the ATP content of cells . Feeding of glucose to such starved cell cultures caused the cells to restore both the ATP content and the ability to form blender-resistant phage-cell complexes . Such restoration was also observed when the starved cells collected by centrifugation were incubated in a glucose-containing medium . The significance of the intracellular level of high energy compounds such as ATP for the mechanism of the injection of phage genomes into the cells is discussed. Microbiol Immunol, 1979, 23(10), 941 - 53 Ultrastructure and partial characterization of a regular array in the cell wall of Lactobacillus brevis; Masuda K et al.; The cell wall of Lactobacillus brevis was revealed by electron microscopy to have an outer layer composed of a regular array . The morphological unit of the regular array appeared to consist of four spherical subunits, each about 2 nm in diameter, which were arranged in a tetragonal pattern about 4.5 by 7.0 nm in dimension . The regular array was composed of the tetragonal units in rows in two directions at an angle of about 75 degrees to each other . The average spacing between the rows was about 10 nm in one direction and about 7 nm in the other . The tetragonally arranged subunits were removed from the cell wall by treatment with guanidine hydrochloride, urea, or sodium dodecyl sulfate (SDS) but not by the action of ethylenediaminetetraacetate, nonionic detergents, or proteolytic enzymes except pepsin . The regular subunits were shown to be composed of a protein with a molecular weight of about 51,000 by SDS-polyacrylamide gel electrophoresis. J Egypt Public Health Assoc, 1979, 54(1-2), 49 - 63 Statistico epidemiological study of changes in the vaginal flora of contraceptive pill users in Alexandria; Fares E et al.; PIP: A stratified random sample of 1000 women with proportionate allocation according to district of residence was taken from normal females living in Alexandria, Egypt, and attending family planning centers in order to understand social-pathological changes in the vaginal flora of oral contraceptive (OC) users . Cases were examined over 18 months, and all cases were given a combined OC . Bacteriology and pH changes in vaginal flora were determined after 18 months . Results of the bacteriological examination revealed a positive correlation between those having a vaginal discharge and pH above 5, mixed infection, and illiteracy . As the duration of pill use increased, so did the incidence of monilla, staphylococcus aureus, anaerobic streptococci, gram negative bacilli, trichomonas vaginalis, and hemophilus vaginalis, whereas lactobacilli decreased . Duration of pill use also corresponded to increase in vaginal pH . Longer duration of OC use, practice of bad hygiene, and illiteracy were factors associated with an alkaline pH, changed pattern of vaginal flora, and greater susceptibility to infection by staph aureus and E . coli . Acta Odontol Scand, 1979, 37(2), 103 - 15 Effects of 3 months frequent consumption of hydrogenated starch hydrolysate (Lycasin), maltitol, sorbitol and xylitol on human dental plaque; Birkhed D et al.; Lozenges containing hydrogenated starch hydrolysate (Lycasin), maltitol, sorbitol or xylitol were consumed 4 times daily during 3 months by 4 groups of persons (in all 85 subjects) . In the maltitol-, sorbitol- and xylitol-group the plque wet weights were of the same magnitude before and after the test period . In the Lycasin-group, a higher value was found after than before the 3-month period (p less than 0.01) . The acid production in suspensions of dental plaque material from Lycasin, maltitol and sorbitol expressed as per cent of that from glucose was approximately the same before and after the test period . From xylitol no acid production could be demonstrated either before or after the 3-month period . There were no statistically significant differences between the plaque pH-changes induced by rinsing with 50% solutions of Lycasin, maltitol, sorbitol or xylitol before and after the test period . However, there was a tendency (p less than 0.05) towards lower pH-values induced by the maltitrol and sorbitol rinse after the 3-month period compared with before . No difference in the relative numbers of facultative anaerobic streptococci . Streptococcus mutans or facultative anaerobic lactobacilli before and after the test period was found. Gut, 1978 Dec, 19(12), 1099 - 104 Influence of inflammatory bowel disease on intestinal microflora; Keighley MR et al.; The microflora of the jejunum, ileum, and colon has been studied from operative samples in Crohn's disease (n = 30), ulcerative colitis (n = 15), and controls (n = 40) . There was no significant difference in the flora of patients with ulcerative colitis compared with controls . In Crohn's disease there was a significant increase in E . coli (P less than 0.001) and B . fragilis (P less than 0.001) in the ileum and of E . coli (P less than 0.001) and lactobacilli (P less than 0.01) in the colon . The abnormal ileal flora in Crohn's disease was unrelated to serological evidence of disease activity (indices: ESR, serum albumin, serum seromucoids), diameter of the ileum, or excision of the ileocaecal valve . The abnormal colonic flora in Crohn's disease was not related to presence of macroscopic colitis. Clin Chem, 1978 Dec, 24(12), 2192 - 6 Comparison of radioassay and microbiological assay for serum folate, with clinical assessment of discrepant results; Baril L et al.; Folate assays by use of radiolabeled folate provide obvious practical advantages over the standard microbiological assay, but remain incompletely tested . We therefore compared results for 415 sera with a kit involving 3H-labeled folate and the Lactobacillus casei microbiological method . We examined the patients' data when there were discrepancies between the two methods . Although the correlation overall was satisfactory, results were discrepant in 25% of cases . In 74% of the latter, the radioassay result appeared to be the correct one, primarily because L . casei results were suppressed by antibiotics being taken by the patient . The radioassay occasionally gave falsely high values for patients with liver disease and falsely low ones for patients who had received isotopes for scanning purposes . Several assay kits that make use of 125I- or 75Se-labeled folate were also tested . Although these results correlated with the results of 3H-labeled folate assay, various problems appeared, including the possible need for serum-supernate control tubes in one kit . Answers to these and other questions and careful clinical correlation of results are needed for any folate radioassays before their adoption for routine clinical use. Z Lebensm Unters Forsch, 1978 Nov 28, 167(5), 342 - 54 {The microflora of sour dough . IV . Communication: bacterial composition of sourdough starters genus Lactobacillus beijerinck (author's transl)}; Spicher G et al.; The bacterial composition of three so called pure culture sourdough starters of varying origin was investigated . 245 isolates were obtained all belonging to the genus Beijerinck . According to their morphological, physiological and biochemical characteristics they were classified into the subgroups: Thermobacterium (L . acidophilus), Streptobacterium (L . casei, L . plantarum, L . farciminis, L . alimentarius) and Betabacterium (L . brevis, L . brevis var . lindneri, L buchneri, L . fermentum, L . fructi vorans) . In the three sourdough starters the identified lactic organisms varied in number and proportion . In starter preparation "A" only the varieties L . fructi vorans and L . fermentum were present . Preparation "B" contained a great variety of microorganisms with L . brevis and L . brevis L . lindneri predominating . In starter "C" L . brevis, L . plantarum and L . alimentarius predominated. Obstet Gynecol, 1978 Nov, 52(5), 601 - 4 Cervical-vaginal flora of women with invasive cervical cancer; Mead PB; The cervical-vaginal flora of 21 women with invasive cervical cancer was determined . The cultures yielded polymicrobial growth with anaerobic organisms predominating . As compared with other studies of vaginal flora, the cancer patients were found to have a decreased frequency of isolation of aerobic lactobacilli, Staphylococcus epidermidis, and enterococci, and an increased frequency of isolation of Escherichia coli and Bacteriodes species . The composition of the anaerobic vaginal flora in these patients is similar to that described for immunosuppressed renal transplant patients. Med Microbiol Immunol (Berl), 1978 Oct 20, 165(3), 139 - 45 Cervical bacterial flora in infertile and pregnant women; Moberg P et al.; The cervical bacterial flora in early pregnancy, labour, and infertility was assessed qualitatively . The cervix harboured several types of bacteria in both pregnant and infertile women . In the latter group, however, fewer species were found . The incidence of a mixed aerobic and anaerobic flora differed significantly between patient categories as did the frequency with which only aerobic isolates were obtained . There was also a significant difference between patient groups with regard to the incidence of anaerobic isolates . Among the anaerobic bacteria, peptostreptococci and bacteroides species were the dominating ones whereas coagulase-negative staphylococci were the most prevalent aerobic bacteria . Lactobacilli constituted 29--44% of the anaerobic bacteria found in the pregnant cervix and 52% of those found in the infertile cervix . The distribution of different aerobes as well as anaerobes was similar in pregnant and infertile patients. J Dairy Res, 1978 Oct, 45(3), 445 - 55 Peptide hydrolases of Lactobacillus casei: isolation and general properties of various peptidase activities; El Soda M et al.; Discovery of an endopeptidase by gel chromatography and separation of 3 exopeptidases (a dipeptidase, an aminopeptidase and a specific carboxypeptidase) from Lactobacillus casei NCDO 151 by affinity chromatography is described . The 3 exopeptidases were strongly inhibited by the metal chelators EDTA and 1,10-phenanthroline but were reactivated with Co2+ and Mn2+ . The pH optima for aminopeptidase, dipeptidase and carboxypeptidase activities were 6.5, 7.6 and 7.2, respectively . Maximum activity was obtained at 45 degrees C for the aminopeptidase, at 30 degrees C for the dipeptidase and at 40 degrees C for the carboxypeptidase . The substrate specificities of the 3 enzymes were also studied . The properties of these 3 enzymes are compared with those of other bacteria. J Biol Chem, 1978 Sep 25, 253(18), 6437 - 44 Dihydrofolate reductase from amethopterin-resistant Lactobacillus casei . Sequences of the cyanogen bromide peptides and complete sequences of the enzyme; Freisheim JH et al.; The complete amino acid sequence of dihydrofolate reductase from an amethopterin-resistant strain of Lactobacillus casei has been determined by sequence analysis of peptides produced by cleavage with cyanogen bromide, trypsin, staphylococcal protease, and myxobacter protease . Comparison of this sequence with those of reductases from other bacterial sources shows that the enzymes are homologous . The Lactobacillus casei reductase sequences shows a 29% sequence identity with that of the Escherichia coli enzyme and a 34% identity with the sequence of the enzyme from Streptococcus faecium . The NH2-terminal 68 residues of the L . casei reductase show a 54% sequence identity with that of the enzyme from S . faecium. Zh Mikrobiol Epidemiol Immunobiol, 1978 Sep, (9), 52 - 4 {Antibiotic and sulfanilamide resistance of the coli- and lactobacteria used for the production of bacterial preparations}; Blant ME et al.; An antibiotic-resistant mutant recommended for the production of colibacterin preparation was isolated from the E . coli strain M-17 highly-sensitive to antibiotics . A possibility of complex use of bacterial preparations (coli- and lactobacterin) with antibiotics and sulphanylamides for prevention of dysbacteriosis was demonstrated. Arch Neurol, 1978 Sep, 35(9), 581 - 4 Polyneuropathy and folate deficiency; Botez MI et al.; We studied five patients (two men and three women, age between 58 and 76 years) with clinical and electrophysiological signs of polyneuropathy . Routine neurological, hematological, and gastroenterological studies as well as procedures to test fat malabsorption were performed . Folate determinations were done using both radioactive and Lactobacillus casei methods . Two patients displayed the signs of subacute combined degeneration of the spinal cord with polyneuropathy, while three had only signs of neuropathy . All had low serum folate concentration, long-standing gastrointestinal disease, and deficient folate intake . The D-xylose absorption test gave values in all patients, while none displayed the classical malabsorption syndrome . The patients had substantial improvement or recovered (according to clinical and electrophysiological measurements) after periods ranging from 9 to 39 months of folate therapy . Such acquired folate-responsive polyneuropathy has two principal characteristics: mixed sensorimotor with mainly sensory deficits, and involvement of one or both of the lower extremities much more extensively than the upper extremities. Am J Clin Pathol, 1978 Sep, 70(3), 359 - 63 Measurement of serum folate by 75Se-selenofolate radioassay . Results of a multi-institutional clinical trial; Waxman S et al.; The authors report the multi-institutional evaluation of a radioassay for serum folate utilizing a gamma-labeled folate analog (75Se-pteroyl-L-methylselenocysteine) . The assay is run as a one-step simultaneous addition at ambient temperature and is completed within 45 minutes . The assay data were reproducible within four study centers and correlated with both the Lactobacillus casei diagnostic groups and the clinical pictures. J Nucl Med, 1978 Aug, 19(8), 906 - 12 Measurement of folates in human plasma and erythrocytes by a radiometric microbiologic method; Chen MF et al.; A radiometric microbiologic assay for the determination of folic acid in human plasma and red blood cells is described . The assay is based upon the measurement of 14CO2 produced from the metabolism of {1-14C} gluconate by Lactobacillus casei . The 14CO2 evolved was shown to be proportional to the amount of added DL-N-5-methyltetrahydrofolage (DL-N-5-methyl FH4) . A total of 26 normal plasma and 57 blood hemolysates were assayed in parallel by this radiometric and the standard (turbidimetric) microbiologic assay . The correlation coefficients for the two assays were r = 0.96 for plasma and r = 0.98 for red-cell folate . Lyophilization of L . casei was found to simplify this radiometric assay by eliminating routine maintenance and culture of this microorganism. Eur J Biochem, 1978 Jul 17, 88(1), 175 - 81 Reaction mechanism of non-allosteric phosphofructokinase; Simon WA et al.; The reaction mechanism of the non-allosteric phosphofructokinase from Lactobacillus plantarum was investigated by initial-rate bisubstrate kinetics and product inhibition kinetics adn by the measurement of equilibrium isotope exchange in the presence of various substrate and product concentrations . The reaction mechanism is clearly sequential . The product inhibition and equilibrium isotope-exchange patterns are consistent with an ordered bi-bi reaction sequence with fructose 6-phosphate as the leading substrate and ADP as the first product released from the enzyme. J Gen Microbiol, 1978 Jul, 107(1), 139 - 45 Deoxyribonucleoside-requiring mutants of Bacillus subtilis; Rima BK et al.; A number of deoxyribonucleoside-requiring mutants (dns) of Bacillus subtilis were isolated and their growth characteristics and ribonucleotide reductase activities were compared with those of the wild type and of a dna mutant (tsA13) . Both tsA13 and dns mutants required the presence of a mixture of deoxyribonucleosides for growth at 45 degrees C but not at 25 degrees C . All the mutant strains tested contained ribonucleotide reductase activity which showed heat sensitivity similar to that of the enzyme from a wild-type strain . The reductase in B . subtilis seemed to reduce ribonucleoside triphosphates in a similar manner to the enzyme in Lactobacillus leichmannii. Int J Gynaecol Obstet, 1978 Jul-1979 Aug, 17(1), 19 - 22 Aerobic and anaerobic cervical flora of healthy Thai women; Jayanetra P et al.; The bacteriologic study of the cervical flora in 50 healthy women revealed that 70% harbored mixed aerobic and anaerobic organisms . Aerobic organisms alone were recovered in 15 women (30%) . Polymicrobial organisms were found in all but five women (in these only one aerobe was isolated per patient) . The majority of patients had 1-2 anaerobes, with more than two aerobes . The common aerobes were alpha-hemolytic streptococci, Staphylococcus epidermidis and lactobacilli . The most common anaerobes were Peptococcus asaccharolyticus isolated in 21 women (42%), P prevotii in 13 (26%) and Bacteroides in 10 (20%) . These organisms are frequently found in pelvic infection, suggesting the pathogenic potential of the normal flora of the cervix. J Dairy Res, 1978 Jun, 45(2), 247 - 57 Lactostrepcins--acid bacteriocins produced by lactic streptococci; Kozak W et al.; All 47 non-nisin producing strains of Streptococcus lactis and 12/13 strains of Str . lactis subsp . diacetylactis examined produced bacteriocins, for which the term lactostrepcins is suggested . Seven strains of Str . cremoris examined produced no bacteriocins active against 3 lactic streptococci strains used as indicators . The strains examined were divided into 3 groups: I, those producing lactostrepcins active against only one streptomycin resistant mutant of Str . lactis 60 indicator strain; II, those producing lactostrepcins active against all 3 indicator strains; III, those not producing lactostrepcins active against the indicator strains employed . The lactostrepcins were sensitive to various proteolytic enzymes and to phospholipase D, but retained full or partial activity after dialysis . Most of the bacteriocins studied were fully active only within the pH range 4.2--5.0 and were reversibly inactivated at pH 7.0 or 8.0 . Results suggested occurrence of 4 different lactostrepcins . The lactostrepcins produced by all group I strains were the same, but there were differences among the lactostrepcins produced by group II strains . Lactostrepcins killed some beta-haemolytic streptococci and some strains of Lactobacillus helveticus . One of the lactostrepcins was also active against certain Leuconostoc strains, but not against other Leuconostoc strains, nor against L . helveticus or other Gram-positive bacteria. Strahlentherapie, 1978 May, 154(5), 342 - 8 {Study of combined injuries (23rd communication) (author's transl)}; Werdan K et al.; NMRI-mice which were whole-body irradiated, received two or three days later open skin wounds . While irradiation or wounding alone caused a mortality of 10 to 20% and 0% respectively, a combination of injuries caused 80 to 100% mortality . With regard to the as yet unexplained pathogenesis of this clinical condition, bacteriological examination of the skin-wound was undertaken . Staphylococci, lactobacilli and gramnegative bacilli were found on the wounds, and the bacterial concentration per cm2 wound area among animals with combined injuries was significantly higher than in controls . Covering the wounds with lint effected a distinct reduction of bacterial number as well as a reduction of mortality . A similar success of therapy was attained through local administration of antibiotics . A possible correlation between bacterial seeding and increased mortality is discussed. Am J Med, 1978 May, 64(5), 808 - 13 Lactobacillemia--report of nine cases . Important clinical and therapeutic considerations; Bayer AS et al.; Serious infections due to lactobacilli have been rarely cited . We report our findings in nine recent patients with lactobacillemia . In the combined literature and current experience, endocarditis and sepsis from localized suppuration were the most common clinical syndromes, most frequently arising from prior oropharyngeal infections . Lactobacillus endocarditis showed a predilection for left-sided cardiac involvement (100 per cent) and systemic arterial embolization (55 per cent) . The nine clinical isolates were tested for minimal inhibitory and bactericidal concentrations (MICs and MBCs) against five drugs with broad gram-positive spectrums; of note, these organisms demonstrated a high incidence of both unachievable MBCs (64 per cent) and widely disparate (greater than 100 fold) MIC:MBC ratios (38 per cent) . This is in accord with observations in Lactobacillus endocarditis of poor in vivo clinical response despite "appropriate" regimens and achievable MICs of the organisms . Bactericidal synergistic studies on two endocarditis isolates indicated that the penicillins plus aminoglycosides may be potentially useful in the treatment of deep-seated Lactobacillus infections when single antimicrobials fail to achieve a cure. Gastroenterology, 1978 May, 74(5 Pt 1), 829 - 30 Effect of a lactobacilli preparation on traveler's diarrhea . A randomized, double blind clinical trial; de dios Pozo-Olano J et al.; The effectiveness of prophylactic ingestion of a commercial preparation of lactobacilli (Lactinex) for the prevention or modification of traveler's diarrhea was tested in a randomized double blind clinical trial in 50 volunteer travelers to Mexico from the United States . Twenty-six subjects received the lactobacilli preparation and 24 received placebo . The incidence of diarrhea and its duration during the 4 weeks of observation were quite similar for the two preparations: 35% for lactobacilli-treated subjects and 29% for placebo subjects . Typically, the diarrhea was mild, lasting 2 days . From the observations during this study we conclude that prophylactic ingestion of lactobacilli for 1 week does not reduce the incidence or duration of traveler's diarrhea either during the period of ingestion or during the following 3 weeks. Biochem J, 1978 May 1, 171(2), 357 - 66 Ultraviolet difference-spectroscopic studies of substrate and inhibitor binding to Lactobacillus casei dihydrofolate reductase; Hood K et al.; The u.v . difference spectra generated when methotrexate, trimethoprim or folate bind to Lactobacillus casei dihydrofolate reductase were analysed . The difference spectrum producted by methotrexate binding is shown to consist of three components: (a) one closely resembling that observed on protonation of methotrexate, reflecting an increased degree of protonation on binding; (b) a pH-independent contribution corresponding to a 40 nm shift to longer wavelengths of a single absorption band of methotrexate: (c) a component arising from perturbation of tryptophan residue(s) of the enzyme . Quantitative analysis of the pH-dependence of component (a) shows that pK of methotrexate is increased from 5.35 to 8.55 (+/-0.10) on binding . In contrast, folate is not protonated when bound to the enzyme at neutral pH . At pH7.5, where methotrexate is bound 2000 times more tightly than folate, one-third of the difference in binding energy between the two compounds arises from the difference in chaarge stage . A similar analysis of the difference spectra generated on trimethoprim binding demonstrates that this compound, too, shows an increase in pK on binding but only from 7.22 to 7.90 (+/-0.10), suggesting that its 2,4-diaminopyrimidine ring does not bind to the enzyme in precisely the same way as the corresponding moiety of methotrexate. Biochim Biophys Acta, 1978 Apr 26, 533(2), 415 - 27 Binary and ternary complexes of dihydrofolate reductase with substrates, coenzymes and inhibitors . Circular dichroic and magnetic circular dichroic studies; Reddy AV et al.; Interaction of several representative folate, quinazoline and pyridine nucleotide derivatives with dihydrofolate reductase from amethopterin-resistant Lactobacillus casei induces dramatic changes in its circular dichroic spectral properties . The binding of dihydrofolate induces a large extrinsic Cotton effect at 295 nm ({theta} = 113 800 deg . cm2 . dm-1) . The generation of this band by dihydrofolate is strictly dependent on complex formation with a single substrate binding site and a KD = 7 . 10(-6) M . The other binary complexes examined include the enzyme . NADPH, enzyme . amethopterin, enzyme . folate, and enzyme . methasquin . All such complexes differ in spectral detail, the negative ellipticity at 330 nm being characteristic of the "folate site" complexes . The circular dichroic spectrum of the ternary complex of reductase . NADPH . methotrexate shows a positive symmetrical band centered at 360 nm ({theta} - 32 000 deg . cm2 . dm-1) . Since both of the corresponding binary complexes exhibit negative bands in this region, this induced band represents a unique molecular property of the ternary complex . Chemical modification of a single tryptophan residue of the enzyme, as determined from magnetic circular dichroism spectra, results in a complete loss in the ability to bind either dihydrofolate or NADPH. Hoppe Seylers Z Physiol Chem, 1978 Apr, 359(4), 473 - 80 Comparison of tRNA nucleotidyltransferase from Escherichia coli and Lactobacillus acidophilus; Leineweber M et al.; Purification of tRNa nucleotidyltransferase from Lactobacillus acidophilus ATCC 4963 and Escherichia coli MRE 600 by preparative polyacrylamide gel electrophoresis is described . Both enzymes gave a single band on analytical polyacrylamide-gel electroesis and sodium dodecylsulfate gels . Chromatography of the high speed supernatant from Lactobacillus at low salt concentrations gave three enzyme fractions of molecular weights about 45 000, 90 000, and 120 000 . At 1M NaCl only the first enzyme fraction was found . Kinetic data for both enzymes are given. J Pharm Sci, 1978 Apr, 67(4), 520 - 6 Effect of acylated amino acids and acylated amino acid analogs on microbial antitumor screen; Otani TT et al.; A series of N-acetyl,-N-propionyl, and N-chloroacetyl derivatives of amino acids and amino acid analogs was tested for growth-inhibitory activity using a Lactobacillus casei system as a prescreen for possible antitumor activity . While none of the acetyl or propionyl derivatives of these amino acids and amino acid analogs caused any remarkable inhibition, certain chloroacetyl derivatives exhibited significant activity . The chloroacetyl derivatives, especially those of essential amino acids and of analogs of essential amino acids, showed modest, but pharmacologically significant, inhibition; those of nonessential amino acids exhibited no activity . When two such inhibitory acyl derivatives were combined in a single assay, the extent of inhibition was neither additive nor synergistic but was that of the more active of the two test components. Biochim Biophys Acta, 1978 Mar 30, 528(3), 298 - 308 On the relationship between glycerophosphoglycolipids and lipoteichoic acids in Gram-positive bacteria . II . Structures of glycerophosphoglycolipids; Fischer W et al.; 1 . Eight glycerophosphoglycolipids were isolated from six Gram-positive bacteria . Besides sn-glycero-1-phospho-beta-gentiobiosyldiacylglycerol (i) and sn-glycero-1-phospho-alpha-kojibiosyldiacylglycerol (ii), three novel structures have been established: 1,2-di-O-acyl-3-O-{6-(sn-glycero-1-phospho)-alpha-D-glucopyranosyl-(1 leads to 2)-(6-O-acyl-alpha-D-glucopyranosyl)}glycerol (iii), 1,2-di-O-acyl-3-O-{6-(sn-glycero-1-phospho)-beta-D-glucopyranosyl-(1 leads to 6)-alpha-D-galactopyranosyl-(1 leads to 2)-alpha-D-glucopyranosyl}glycerol (iv), and 1,2-di-O-acyl-3-O-{6-(sn-glycero-1-phospho)-beta-D-glucopyranosyl-(1 leads to 6)-alpha-D-galactopyranosyl-(1 leads to 2)-(6-O-acyl-alpha-D-glucopyranosyl)}glycerol (v) . 2 . Compound i was isolated from Bacillus licheniformis, Bacillus subtilis and Staphylococcus aureus, compound ii from a group B Streptococcus, compounds ii and iii from Streptococcus lactis, compounds iv and v from Lactobacillus casei . Lactobacillus plantarum contained besides compounds iv and v a glycerophosphate derivative of 1,2-di-O-acyl-3-O-{alpha-D-galactopyranosyl (1 leads to 2)-alpha-D-glucopyranosyl}glycerol . 3 . Identical structural features of the described glycerophosphoglycolipids and the corresponding lipoteichoic acids are discussed. Biochemistry, 1978 Mar 21, 17(6), 1010 - 4 Mechanism of inactivation of ornithine decarboxylase by alpha-methylornithine; O'Leary MH et al.; Ornithine decarboxylase from Lactobacillus 30a is gradually inactivated by treatment with alpha-methylornithine, but activity is restored by treatment of the inactivated enzyme with pyridoxal phosphate . Inactivation of the enzyme is associated with formation of pyridoxamine phosphate and 5-amino-2-pentanone, alpha-Methylornithine is decarboxylated by the enzyme about 6000 times more slowly than is ornithine under the same conditions . These observations provide an explanation for the previously observed inhibition of ornithine decarboxylase by alpha-methylornithine {M . M . Adbel-Monem, N . E . Newton, and C . E . Weeks (1974), J . Med . Chem . 17, 4447}: alpha-Methylornithine undergoes a decarboxylation-dependent transamination as a result of incorrect protonation of the quinoid intermediate which is formed by decarboxylation of the enzyme-bound pyridoxal phosphate-substrate Schiff base . This protonation produces inactive enzyme . Decarboxylation of ornithine by this enzyme produces a small amount of 4-aminobutanal, presumably also by decarboxylation-dependent transamination. Appl Environ Microbiol, 1978 Mar, 35(3), 582 - 91 Bacteria associated with the gastric epithelium of neonatal pigs; Fuller R et al.; Light and electron microscopy showed lactobacilli and, to a lesser degree, streptococci to be closely associated with the squamous area of the pig stomach known as the pars esophagea . Several different types of extracellular layers were seen on bacteria attached to the epithelial surface . The total number of bacteria per square centimeter did not change with age up to 10 days, and there was no effect of weaning at 2 days . Lactobacillus fermentum, L . salivarius, and Streptococcus salivarius were isolated more frequently from sucking pigs than from those that were early weaned, whereas the reverse was true of L . acidophilus and S . bovis . All isolates recovered from washed macerated pars esophagea adhered to pig esophageal epithelial cells when tested in vitro. J Clin Pathol, 1978 Mar, 31(3), 227 - 9 Effect of Tween 80 on incubation period of Lactobacillus casei assay of serum folate; Tennant GB; Contamination of folic acid assay medium with oleate led to a lag phase when Lactobacillus casei cultures were grown on folic acid but not when whole serum provided the folate source . This led to high assay values when using 20-hour incubation periods but satisfactory results were obtained after 48 hours' incubation . The addition of Tween 80 to the medium eliminated the lag phase and the assay results were consistent after 13, 24, and 48 hours' incubation. J Bacteriol, 1978 Mar, 133(3), 1190 - 6 Binding and transport of thiamine by Lactobacillus casei; Henderson GB et al.; The relationship between thiamine transport and a membrane-associated thiamine-binding activity has been investigated in Lactobacillus casei . Thiamine transport proceeds via a system whose general properties are typical of active uptake processes; entry of the vitamin into the cells requires energy, is temperature dependent, exhibits saturation kinetics, and is inhibited by substrate analogs . A considerable concentration gradient of unchanged thiamine can be achieved by the system, although the vitamin is slowly metabolized to thiamine pyrophosphate . Consistent with these results, L . casei also contains a high-affinity, thiamine-binding component which could be measured by incubation of intact cells with labeled substrate at 4 degrees C (conditions under which transport is negligible) . Binding was insensitive to iodoacetate, occurred at a level (0.5 nmol per 10(10) cells) nearly 20-fold higher than could be accounted for by facilitated diffusion, and was found to reside in a component of the cell membrane . Participation of this binder in thiamine transport is supported by the observations that the processes of binding and transport showed similarities in their (i) regulation by the concentration of thiamine in the growth medium, (ii) binding affinities for thiamine, and (iii) susceptibility to inhibition by thiamine analogs. Poult Sci, 1978 Mar, 57(2), 392 - 7 In vitro antibiotic susceptibility of enteric bacteria isolated from commercial broiler chickens; Kitai K et al.; The in vitro activity of six different antimicrobial agents was evaluated by an agar dilution method against enteric bacteria isolated from broilers . Of 923 isolates, 796 were gram-positive bacteria and 127 were Escherichia coli (E . coli) . Thiopeptin at 25 microgram/ml inhibited 75% of lactobacilli . This antibiotic at .78 microgram/ml inhibited 82% of staphylococci and more than 92% of other gram-positive organisms . Bacitracin at 100 microgram or less per ml was active against 42% of staphylococci and 30% of streptococci . At 6.25 microgram or less per ml, 70% of clostridia and 78% of lactobacilli were inhibited . The minimum inhibitory concentrations (MIC) of penicillin G and ampicillin shown as cumulative distribution curves for all isolates were very similar . Both antibiotics showed a wide range of MIC distribution . Streptomycin at 50 microgram or less per ml was active against 87% of lactobacilli and 50% of E . coli . Only 32% of staphylococci were inhibited at these concentrations . At 100 microgram or less per ml, 30% of streptococci and 12% of clostridia were inhibited . Tetracycline at 100 microgram or less per ml inhibited 63% of clostridia . Lactobacilli and E . coli were not inhibited by this antibiotic at 100 microgram or less per ml. Infect Immun, 1978 Feb, 19(2), 704 - 10 Inhibition of Neisseria gonorrhoeae by aerobic and facultatively anaerobic components of the endocervical flora: evidence for a protective effect against infection; Saigh JH et al.; The ability of aerobic and facultatively anaerobic endocervical flora to inhibit the growth of Neisseria gonorrhoeae in vitro was assayed . Factors influencing the occurrence of inhibitory components of the flora in vivo were evaluated . Endocervical swabs were obtained from 229 women at a local venereal disease clinic . Endocervical flora and N . gonorrhoeae were isolated and identified, and the ability of the flora to inhibit the growth of N . gonorrhoeae was determined by an agar overlay assay . Results revealed the most active inhibitors to be streptococci, staphylococci, and lactobacilli, in that order . Among only those women harboring inhibitory endocervical flora, inhibitory lactobacilli were recovered from fewer women infected with N . gonorrhoeae than uninfected women (P less than 0.05) . Among women having contact with an infected partner, those who subsequently developed gonorrhea were less likely to have inhibitory lactobacilli than those who did not become infected (P less than 0.05) . No other significant differences in the composition of the inhibitory flora were noted between infected and uninfected women . During the 2 weeks following menses, recovery of inhibitory lactobacilli on culture was highest, whereas recovery of N . gonorrhoeae was lowest . These observations suggest that the presence of certain lactobacilli may reduce risk of acquisition of N . gonorrhoeae following exposure to infected partners and that the potential protective effect may be greatest during the 2 weeks after menses. Am J Clin Pathol, 1978 Feb, 69(2), 137 - 9 Effects of antineoplastic drugs on Lactobacillus casei and radioisotopic assays for serum folate; Carmel R; Microbiologic assay, usually employing Lactobacillus casei, remains the standard assay for serum folate to date . Among its disadvantages have been falsely low results in patients receiving bacteriostatic agents such as antibiotics . This study examined whether commonly used antineoplastic drugs had similar effect . Methotrexate and 5-fluorouracil depressed microbiologic serum folate levels . No effect was found for adriamycin, bleomycin, BCNU, cyclophosphamide, cytosine arabinoside, vincristine, vinblastine, mechlorethamine, mithramycin, hydroxyurea, and hydrocortisone . None of the drugs affected radioassay except methotrexate, which produced falsely high folate results . Thus, it appears that L . casei assay for folate becomes unreliable in patients receiving 5-fluorouracil and radioisotopic assay becomes unreliable in those receiving methotrexate. Scand J Gastroenterol, 1978, 13(3), 345 - 7 Endoscopy-related bacteremia; Stray N et al.; A prospective study was undertaken to investigate the frequency of bacteremia after endoscopy of the gastrointestinal tract . In one out of 100 patients undergoing gastroscopy and in one out of 25 patients undergoing coloscopy, positive blood cultures could be demonstrated . In both cases anaerobe lactobacilli were recovered . No bacteremia was demonstrated in 25 patients undergoing endoscopic retrograde cholangiopancreatography (ERCP). Prep Biochem, 1978, 8(2-3), 91 - 8 Nalpha-(pteroyltetra (gamma-glutamyl))-lysine as a ligand for the purification of thymidylate synthetase by affinity chromatography; Plante LT et al.; Nalpha-(pteroyltetra (gamma-glutamyl))-lysine Sepharose was synthesized and shown to be a stable high capacity affinity matrix capable of bringing about the purification of Lactobacillus casei thymidylate synthetase to maximum specific activity from crude extracts in high yield . Under conditions optimal for binding of thymidylate synthetase, dihydrofolate reductase was not bound. Microbiol Immunol, 1978, 22(6), 301 - 14 Dental caries induction in experimental animals by clinical strains of Streptococcus mutans isolated from Japanese children; Hamada S et al.; Oral implantation and the cariogenic activity of clinical strains of Streptococcus mutans which had been isolated from Japanese children and labeled with streptomycin-resistance were examined in specific pathogen-free Sprague-Dawley rats . All the seven strains tested were easily implanted and persisted during the experimental period . Extensive carious lesions were produced in rats inoculated with clinical strains of S . mutans belonging to serotypes c, d, e, and f, and maintained on caries-inducing diet no . 2000 . Noninfected rats did not develop dental caries when fed diet no . 2000 . Type d S . mutans preferentially induced smooth surface caries in the rats . Strains of other serotypes primarily developed caries of pit and fissure origin . Caries also developed in rats inoculated with reference S . mutans strains BHTR and FAIR (type b) that had been maintained in the laboratories for many years . However, the cariogenicity of the laboratory strains was found to have decreased markedly . All three S . sanguis strains could be implanted, but only one strain induced definite fissure caries . Two S . salivarius strains could not be implanted well in the rats and therefore they were not cariogenic . Four different species of lactobacilli also failed to induce dental caries in rats subjected to similar caries test regimen on diet no . 200 . S . mutans strain MT6R (type c) also induce caries in golden hamsters and ICR mice, but of variable degrees. Zentralbl Bakteriol {Orig B}, 1978 Jan, 166(1), 105 - 11 Lactobacilli isolated from French saucisson (taxonomic study); Laban P et al.; 190 Lactobacilli strains originating from saucisson produced in France, were isolated . The use of numerical taxonomy enabled 6 representative taxa to be established, defined by average biochemical profiles, differing greatly from those of Lactobacilli from dairy origins . Two groups of tests seem to be of particular interest in order to characterize these strains: 1 . Fermentaion of ribose: positive, Arginine dihydrolase: positive, Gas production: negative . 2 . Fermentation of melibiose: positive, Fermentation of raffinose: negative. J Clin Pathol, 1978 Jan, 31(1), 47 - 9 Measurement of red cell folate with 75Se-selenofolate radioassay; Johnson I et al.; 75Se-selenofolate radioassay was adapted for the purpose of red cell folate measurement . The results of assay of 124 whole blood samples by Lactobacillus casei microbiological assay and by radioassay using the adapted selenofolate method were concordant (r = 0.8) . Red cell folate levels by the radioassay were below 170 microgram/1 in people who had haematological features of folate depletion . The distribution of results among reputedly healthy subjects extended down to 140 microgram/1. J Hyg Epidemiol Microbiol Immunol, 1978, 22(4), 428 - 34 Bacteriocin typing of some Lactobacillus species of the subgenus betabacterium; Filippov VA; One hundred and forty cultures of L . fermenti, L . brevis, and L . buchneri were tested by the method of delayed antagonism for sensitivity to 39 bacteriocins produced by lactobacillus strains of different species . According to their bacteriocin sensitivity patterns, 84 L . fermenti, 43 L . brevis and 13 L . buchneri cultures were differentiated into 26, 18 and 10 bacteriocin types, respectively . Bacteriocin typing allows not only intraspecific differentiation of L . fermenti, L . brevis and L . buchneri cultures but also a subdivision of their biochemical-physiological variants. Zentralbl Bakteriol {Orig B}, 1978 Jan, 166(1), 87 - 94 Development of listeria monocytogenes in monoxenic and polyxenic beef minces; Gouet P et al.; The objective of this study was to determine the multiplication possibilities of Listeria monocytogenes in beef minces with a defined microflora (gnotoxenic) . Selective counts were made for each species and each bacterial association for a period of 17 days after inoculation of the axenic meat . The concentration of L . monocytogenes did not increase, but remained constant in monoxenic meats . Associated with Lactobacillus plantarum, the number of Listeria tended to decrease . Conversely, in association with P . fluorescens, L . monocytogenes definitely multiplied, especially in polyxenic meats, the microflora of which is similar to that of conventional meats . Consequently, it seems that meat might constitute a source of L . monocytogenes infection. Hoppe Seylers Z Physiol Chem, 1978 Jan, 359(1), 1 - 11 Trihexosyldiacylglycerol and acyltrihexosyldiacylglycerol as lipid anchors of the lipoteichoic acid of Lactobacillus casei DSM 20021; Nakano M et al.; The lipoteichoic acid of Lactobacillus casei DSM 20021 was isolated . It consists of glycolipid and a poly(glycerophosphate), 37-44 units in length . The lipid portions can be released by treatment with hydrofluoric acid or acetic acid . They were determined to be 1,2-di-O-acyl-3-O-{O-beta-D-glucopyranosyl-(1 leads to 6)-O-alpha-D-galacto-pyranosyl-(1 leads to 2)-alpha-D-glucopyranosyl}glycerol and 1,2-di-O-acyl-3-O-{O-beta-D-glucopyranosyl-(1 leads to 6)-O-alpha-D-galactopyranosyl-(1 leads to 2)-(6-O-acyl-alpha-D-glucopyranosyl)}glycerol . Lipoteichoic acid with a third carbohydrate-linked fatty acid in the glycolipid portion represents a novel subclass. J Clin Microbiol, 1978 Jan, 7(1), 82 - 3 Evaluation of a micromethod for determination of Streptococcus mutans and Lactobacillus infection; Westergren G et al.; A micromethod was developed for quantitative estimation in saliva of Streptococcus mutans and lactobacilli . With a semiautomatic pipette, 25 microliter of diluted saliva was spotted on the surface of an agar plate containing a selective medium . This volume gave a spot with a diameter of about 10 mm in which separate colonies could be counted . The results obtained with the spotting technique showed excellent agreement with those obtained with conventional agar plating . The method is convenient and results in a substantial saving of culture media. Ciba Found Symp, 1978, (67), 211 - 23 Methylglyoxal production in human blood; Brandt RB et al.; The research of Szent-Gyorgyi and others has suggested that the three-carbon ketoaldehyde methylglyoxal has a potential role in the control of cell growth . Its metabolism to D-lactate (not the L-lactate of glycolysis) is catalysed by the mammalian enzymes glyoxalase I (S-lactoyl-glutathione methylglyoxal-lyase, isomerizing; EC 4.4.1.5) and glyoxalase II (S-2-hydroxyacylglutathione hydrolase; 3.1.2.6), with glutathione as a coenzyme . Direct determination of methylglyoxal in biological tissues is difficult because of the active glyoxalase system . However, the product of the glyoxalase system, D-lactate, should indicate formed or added methylglyoxal . A stereospecific assay was used to measure D-lactate in human plasma; it involved the spectrophotometric analysis of NADH at 340 nm catalysed by D-lactate dehydrogenase (D-lactate:NAD+ oxidoreductase; EC 1.1.1.28) from Lactobacillus leichmannii . Blood collected by venepuncture was used for the determination of the plasma concentration of D-lactate . The mean concentration for seven normal subjects was 0.023 mM +/- 0.002 S.E.M . When the glycolytic pathway in whole blood was inhibited in vitro with fluoride, a significant increase in D-lactate was found (about 0.15 mM/hour at 37 degrees C) . Added methylglyoxal also produced an increase in D-lactate formation . Some specific precursors of L-lactate (dihydroxyacetone phosphate, for example) added to whole blood produced an increased concentration of D-lactate, even when glycolysis was not inhibited . This finding indicates that catabolites of glucose lead to methylglyoxal synthesis and suggest a control function for the glyoxalase enzyme system in glycolysis that could be exploited for cancer therapy. J Dent Res, 1978 Jan, 57(1), 65 - 71 8-Hydroxyquinolines with the potential for long-term anticaries activity: design, synthesis, and in vitro evaluation; Mirth DB et al.; 8-Hydroxyquinolyl benzoate and 8-hydroxyquinolyl para-(fluorosulfonyl)benzoate have been synthesized and evaluated in vitro as antimicrobial and antiplaque agents . Both compounds inhibited the growth of cultures of the following genera: Streptococcus, Staphylococcus, Actinomyces, Lactobacillus, Veillonella, and Candida . Minimum inhibitory concentrations ranged from 0.98 to 62 microgram/ml . Extracted human teeth pretreated with 1% solutions of either compound and rinsed with distilled water exhibited reduced in vitro plaque formation for 48 hours . These results indicate that the in vitro antiplaque activity of 8-hydroxyquinolines can be enhanced by attaching the appropriate side chain in the 8-position. Folia Microbiol (Praha), 1978, 23(3), 210 - 5 Lactase activity of microorganisms; Rao MV et al.; Sixty-two strains of yeasts, molds and bacteria were screened for lactase (beta-D-galactosidase) activity . Strains exhibiting the enzyme activity were evaluated for cell yield as well as enzyme units available per litre of the medium, per g cell dry weight and per mg protein of their cell-free extracts . The molds exhibited lowest enzyme activity but highest cell yields, bacteria produced lowest cell yield and maximum enzyme activity . Cultures exhibiting very high activity among yeasts were Saccharomyces fragilis (strain 3217) and among bacteria Streptococcus cremoris (strain H), Lactobacillus bulgaricus (strain RTS and 1373) and Leuconostoc citrovorum (strain 8081). Chemotherapy, 1978, 24(5), 327 - 31 Folate status during long-term therapy with trimethoprim and sulphadiazine; Hjortshoj A et al.; It was studied whether treatment with sulphadiazine and trimethoprim for 8 weeks affected the folate status . The therapy did not inhibit the absorption as assessed by the 3H--folic acid absorption (TRIFA) test . Plasma folic acid clearance showed that folate deficiency had not developed . Bone marrow studies revealed that the antifolic action of the drugs did not manifest itself at the cellular level . The Lactobacillus casei method should not be employed in the determinations of the serum folate concentration during the treatment because therapeutic plasma concentrations of the two drugs inhibit the growth of the test bacteria. Acta Microbiol Pol, 1978, 27(3), 257 - 67 Fluorescent pigments in the newly isolated methylotrophs: Pseudomonas J16 and Methylomonas Pl1; Budohoski L et al.; The pigments showing fluorescence maxima at 390, 366, 450-460 and 520 nm at excitation wavelength 254, 366 and 450 nm respectively, were detected in the cells and culture media of the obligate methylotroph Methylomonas Pl1 and facultative methylotroph Pseudomonas J26 . The maximum at 520 nm is associated with the occurrence of a flavin pigment enabling growth of Lactobacillus casei E ATCC-7469 on the vitamin B2 deficient medium . The remaining fluorescence maxima are related to the prosthetic group of methanol dehydrogenase. Adv Exp Med Biol, 1978, 107, 629 - 37 Effect of growth conditions on the antigenic components of Streptococcus mutans and lactobacilli; Knox KW et al.; 1) The release of LTA from chemostat-grown cultures of S . mutans and L . fermentum is dependent on the generation time and pH . 2) The growth rate affects the immunogenicity of LTA and the wall polysaccharide of L . fermentum . 3) The growth of L . plantarum under glucose limitation influences the glucose content of the wall teichoic acid . The composition of the wall polysaccharide of S . mutans Ingbritt may also be changed under these conditions . 4) The conditions of autoclaving used to release cell wall antigens can hydrolyse the covalent linkage between polysaccharide and peptidoglycan. Mycopathologia, 1977 Dec 31, 62(3), 187 - 9 The formation of germtubes by Candida albicans, when grown with Staphylococcus pyogene, Escherichia coli, Klebsiella pneumoniae, Lactobacilius acidophilus and Proteus vulgaris; Purohit BC et al.; The formation of germtubes by twelve clinical isolates of C . albicans was studied in human serum containing per millilitre 10(3) to 10(9) organisms as: Staphylococcus pyegene, Escherichia coli, Klebsiella pneumoniae, Lactobacillus acidophilus and Proteus vulgaris . All the five bacteria inhibited formation of germtubes by C . albicans at all concentrations and the percent germtube formed diminished with increasing concentration of the bacteria . Lactobacillus acidophilus inhibited the formation of germtubes maximally followed by Staphylococcus pyogene, Escherichia coli and Klebsiella pneumoniae . Proteus vulgaris in the concentrations of 10(3) to 10(7) bacteria per millilitre produced only insignificant inhibition of formation of germtubes by C . albicans . Since germtubes of C . albicans are invasive, it is suggested that inhibition of "blastospore-germtube transformation" may be significantly responsible for prevention of infection by C . albicans by coexisting bacterial flora. Biull Eksp Biol Med, 1977 Dec, 84(12), 709 - 12 {Antitumor effect of glycopeptides from the cell wall of Lactobacillus bulgaricus}; Bogdanov IG et al.; The antitumor activity of "blastolysin", a preparation that consisted mainly of glycopeptide fragments of the cell wall of Lactobacillus bulgaricus, was studied . Blastolysin was found to exert a specific antitumor effect on sarcoma S-180, leukemia P-388, plasmacytoma MOPC-315, adenocarcinoma AKATOL, melanosarcoma B-16, carcinoma LIC, and spontaneous tumors in mice . It is of low toxicity, does not inhibit hemopoiesis, and its action on tumor tissue differs considerably from that of the known antitumor chemotherapeutic agents. Appl Environ Microbiol, 1977 Dec, 34(6), 837 - 42 Isolation and characteristics of a skatole-producing Lactobacillus sp . from the bovine rumen; Yokoyama MT et al.; A bacterium that is capable of decarboxylating indoleacetic acid to skatole (3-methylindole) has been isolated from an L-tryptophan enrichment of bovine rumen fluid . The bacterium is a gram-positive, nonmotile, nonsporeforming rod . It is an obligate anaerobe, and strains predominatly produce D-(-)-lactic acid, with smaller amounts of L-(+)-lactic acid and acetic acid, from sugar . All four strains isolated gave a negative reaction to the indole test because they cannot form skatole directly from tryptophan . This is the first report of indoleacetic acid decarboxylation to skatole in pure culture and the demonstration of skatole production by a Lactobacillus species. J Clin Pathol, 1977 Dec, 30(12), 1168 - 74 Continuous-flow automation of the Lactobacillus casei serum folate assay; Tennant GB; A method is described for the continuous-flow automation of the serum folate assay using Lactobacillus casei . The total incubation period is approximately four hours . The growth response of the organism to folate is estimated by measuring the rate of reduction of 2,3,5-triphenyl tetrazolium chloride (TTC) . A simple continuous culture apparatus is used to grow the inoculum . Supplementation of the assay medium is necessary to obtain parallel results . A statistical assessment shows a favourable comparison with the whole-serum tube assay using a chloramphenicol resistant strain of L . casei . The method is less sensitive to inhibitory substances than the tube assay. J Gen Microbiol, 1977 Dec, 103(2), 261 - 70 Rate-limiting steps in folate metabolism by Lactobacillus casei; Shane B et al.; Oxidation of 5-methyltetrahydrofolate to 5,10-methylenetetrahydrofolate was the rate-limiting step in 5-methyltetrahydrofolate metabolism by Lactobacillus casei . The limiting steps in the utilization of suboptimal levels of folate by L . casei were related to the ability of folates to function in purine and/or thymidylate biosynthesis . Folates with glutamate chains of up to at least seven residues were substrates for these biosynthetic enzymes, and comparisons of bacterial growth yields with transport rates for these folates indicated that the polyglutamates were more effective substrates in purine and thymidylate synthesis than the corresponding pteroylmonoglutamates . Lactobacillus casei contained low levels of a B12-independent, pteroylpolyglutamate-specific methionine synthetase . Its methylenetetrahydrofolate reductase also functioned more effectively with pteroylpolyglutamate substrates. J Gen Microbiol, 1977 Dec, 103(2), 249 - 59 Metabolism of 5-methyltetrahydrofolate by Lactobacillus casei; Shane B et al.; The metabolism of 5-{Me-14 C}methyltetrahydrofolate in Lactobacillus casei proceeded oxidatively with incorporation of label into purine and thymidylate derivatives . No labelled methionine was formed . (l)-5-Methyltetrahydrofolate, the natural isomer, was not a substrate for the L . casei folylpoly-gamma-glutamate synthetase although the unnatural (d)-isomer was slowly metabolized to the diglutamate form. Cancer Treat Rep, 1977 Dec, 61(9), 1657 - 63 A microbiologic disc assay for 5-methyltetrahydrofolate in the presence of methotrexate; Mehta BM et al.; High-dose methotrexate-citrovorum factor rescue regimens are used extensively for the treatment of human malignancies . Since the rescue agent citrovorum factor is rapidly converted to 5-methyltetrahydrofolate, it is desirable to follow the distribution kinetics of both of these coenzymes to assess the selective therapeutic effectiveness of the regimen . The assay methods using methotrexate-resistant strains of Lactobacillus casei ATCC 7469 (LC/A), Streptococcus faecium var . durans ATCC 8043 (SF/A), and Pediococcus cerevisiae ATCC 8081 (PC/A) have been developed to determine the concentrations of 5-methyltetrahydrofolate and other folates in the presence of methotrexate . Since LC/A determines the total folates, SF/A deterimines the total folates except 5-methyltetrahydrofolate, and PC/A by our procedure determines only the most stable form of reduced folates, citrovorum factor, the quantitation of both 5-methyltetrahydrofolate and citrovorum factor can very easily be achieved by differential assays . This report describes the determination of as low as 10 ng/ml of 5-methyltetrahydrofolate in the presence of as high as 500 microgram/ml of methotrexate . The assay method described here is currently used in studying the pharmacokinetics of 5-methyltetrahydrofolate in patients with meningeal neoplasms. Am J Clin Nutr, 1977 Dec, 30(12), 2028 - 32 Reaction of tetrahydrofolic acid with cyanate from urea solutions: formation of an inactive folate derivative; Francis KT et al.; Liver extracts prepared in 6 M urea contain significantly less microbiologically assayable folates than extracts prepared in hot 1% ascorbate . The possibility that inactive folate derivatives are formed by reaction with the cyanate present in the urea solution was investigated . Doubly labeled 2-14C, 3',5',9(n)-3H tetrahydrofolic acid reacted under hydrogen with sodium cyanate gave a compound which, after acidification to remove excess cyanate, shows a single UV absorbing peak at 285 nm . The 14C/3H ratios of starting material and product were the same . Reaction of 14C urea with nonradioactive tetrahydrofolic acid yielded the 14C labeled derivative . The compound does not support Lactobacillus casei growth . It is postulated that folate inactivation in cyanate or thiocyanate treated patients and in uremic patients may have clinical significance. Zentralbl Bakteriol {Orig A}, 1977 Dec, 239(4), 514 - 20 Synthesis of vitamin B12 by various species of mycobacteria; Karasseva V et al.; The synthesis of Vitamin B12 by five reference strains of species of mycobacteria, the influence of cobalt upton the synthesis and the correlation between the phase of growth and quantitative biosynthesis of Vitamin B12 were studied . Assays were performed on cell extracts and culture filtrates using Lactobacillus leichmannii ATCC7830 (tube method) . All five species synthesized Vitamin B12, which could be deomonstrated both in cell extracts and in the culture filtrates . An optimum accumulation of Vitamin B12 by BCG and M . phlei could be observed on the 30th day of cultivation . Addition of cobalt did not influence the growth of BCG and M . phlei, but markedly enhanced the production of Vitamin B12 . Cells contained much more Vitamin B12 than culture filtrates did . Vitamin B12 levels in M . smegmatis, M . fortuitum and M . asiaticum were lower than those in BCG and M . phlei. J Gen Microbiol, 1977 Dec, 103(2), 337 - 44 Specific antigens of Lactobacillus acidophilus; Shimohashi H et al.; Antigens specific for Lactobacillus acidophilus were investigated by double immunodiffusion in agar-gel . Antigenic materials were extracted from whole bacteria and some walls with cold trichloroacetic acid . Antisera were prepared by intravenous injection into rabbits of suspensions of whole organisms in solutions of bovine serum albumin, which had been heated and then washed . Four specific antigens were found as precipitinogens and denoted as antigens 11, 12, 13 and 14 . Of 43 strains of L . acidophilus studied, 33 strains possessed antigen 11, six strains antigen 12, two strains antigen 13 and two strains antigen 14 . Sugar compositions of wall preparations were analysed in an attempt to characterize the determinants of antigens 11 and 12 . The walls contained glucose, galactose, hexosamine and sometimes glycerol, but no rhamnose was found . It was considered that alpha-glucopyranose was the major component of the determinant of antigen 11 since trehalose and maltose significantly inhibited the reaction between antibody 11 and its antigen; the determinant of antigen 12 was not clarified. Infect Immun, 1977 Dec, 18(3), 708 - 16 Binding of lectins to Streptococcus mutans cells and type-specific polysaccharides, and effect on adherence; Hamada S et al.; The lectin concanavalin A (Con A) agglutinated the cells of 13 of 15 strains of the seven serotypes of Streptococcus mutans in an 18-h incubation period . Strains of types a, d, f, and g agglutinated within 2 h . Strains of a, d, and f were also agglutinated in 2 h by the castor bean lectin RCA . S . sanguis, S . salivarius, S . bovis, Actinomyces viscosus, A . naeslundii, and Lactobacillus plantarum were agglutinated within 2 h . The S . mutans type f polysaccharide was precipitated by Con A . The a, b, c, d, and e polysaccharides were not precipitated . Glucan from d and e strains of S . mutans and dextran T2000 were also precipitated by Con A . D-glucose inhibited the agglutination of type f cells by Con A and the agglutination of type d cells by D-galactose . The quantity of {acetyl-3H}Con A bound was not proportional to the degree of agglutination . Cells grown in sucrose medium bound more Con A than those grown in glucose medium . After treatment with dextranase, the sucrose-grown cells bound two- to fourfold more Con A . The binding of Con A to the type-specific polysaccharide or to teichoic acid could not be determined by the use of specific antibody due to the binding of Con A to the antibody globulin on the cell surface . Con A bound to S . mutans cells did not inhibit the activity of cell-bound glucosyltransferase, glucan synthesis, and in vitro adherence . Bound Con A also did not inhibit the ability of heat-treated cells to bind glucosyltransferase, synthesize glucan, and produce in vitro adherence. Nouv Presse Med, 1977 Nov 19, 6(39), 3627 - 8 {Subacute bacterial endocarditis due to lactobacillus (author's transl)}; Dupont B et al.; The case described is one of endocarditis due to lactobacillus casei in a 33-year-old man with aortic insufficiency of undetermined origin . The clinical signs were neurological, following thrombosis of the right posterior cerebral artery . The source of injection was a dental extraction . This case, with a typical clinical picture, is the eleventh to be reported in the literature. Geburtshilfe Frauenheilkd, 1977 Nov, 37(11), 937 - 8 {The purity degree of the vagina containing mycoplasmosis urogenitalis (author's transl)}; Weissenbacher ER et al.; In 156 women with mycoplasmosis urogenitalis the degree of purity of the vagina was determined . In none of the patient's a first degree of purity (containing lactobacilli only) was found . This is an additional sign that mycoplasma has an optional pathogenetic importance in the female urogenital system . In order to restore a normal vaginal flora of lactobacilli, the mycoplasma has to be eliminated. Am J Clin Nutr, 1977 Nov, 30(11), 1777 - 80 Specific adhesion of lactobacilli to keratinized epithelial cells of the rat stomach in vitro; Kawai Y et al.; Indigenous bacteria isolated from rats and chickens demonstrated host specificity in adhering to the keratinized epithelial cells of the rat stomach and the chicken crop epithelium . Of the indigenous bacteria isolated from the rat only lactobacilli and staphylococci attached to the keratinized cells of the rat stomach, suggesting that they are dominant bacteria of the microflora of the stomachs of rats . The effect of the addition of enzymes and other compounds on the adhesion of lactobacilli were investigated . Adhesion was inhibited by treating the lactobacilli with heat, detergents, or certain lipid solvents. J Virol, 1977 Nov, 24(2), 685 - 9 Evidence for frequent lysogeny in lactobacilli: temperate bacteriophages within the subgenus Streptobacterium; Stetter KO; A total of 17 of 21 Lactobacillus strains of the subgenus Streptobacterium were lysogenic . Two different temperate phages isolated from such lysogens are very similar to Lactobacillus casei phage PL-1 . The narrow host range of bacteriophage PL-1 appears to be caused by homoimmunity. J Med Chem, 1977 Nov, 20(11), 1531 - 3 Diastereoisomers of 5,10-methylene-5,6,7,8-tetrahydropteroyl-D-glutamic acid; Kisliuk RL et al.; The diastereoisomers of 5,10-methylene 5,6,7,8-tetrahydropteroyl-D-glutamate were resolved and tested as substrates and inhibitors of Lactobacillus casei thymidylate synthetase . No activity was observed . The compounds were neither growth factors nor inhibitors for Lactobacillus casei, Streptococcus faecium, or Pediococcus cerevisiae . 7,8-Dihydropteroyl-D-glutamate is 50% as active as 7,8-dihydropteroyl-L-glutamate (dihydrofolate) as a substrate for L . casei dihydrofolate reductase. Ann Intern Med, 1977 Nov, 87(5), 542 - 5 The bioavailability of folic acid added to wine; Kaunitz JD et al.; Folate deficiency is a frequent cause of anemia in alcoholics, but little attention has been paid to its prevention . Folic acid was readily soluble in wines of high ethanol content at concentrations of 10 microgram/ml . Lactobacillus casei folate activity of folic acid added to wines was well maintained during a month's storage at room temperature and fell to 61% to 66% of original activity after 3 months . Pteroylglutamic acid, 10 microgram/ml, added to wines and given in doses of the beverages (4 ml/kg body weight that caused inebriation, was well absorbed by six normal human volunteers (mean maximal increment in serum folate concentration +/- SEM, 71 +/- 8 ng/ml) and by seven recently intoxicated chronic alcoholics (mean increment, 94 +/- 4 ng/ml) . Folate deficiency in alcoholics could be prevented by the fortification of alcoholic beverages with the vitamin. Am J Clin Nutr, 1977 Nov, 30(11), 1921 - 6 Properties of the Ames Salmonella mutants lodged in the gastrointestinal tract of gnotobiotic rats; Goldman P et al.; An association of the histidine auxotroph of Salmonella typhimurium (strain TA1538) within the gastrointestinal tract of otherwise germ-free Sprague-Dawley rats is maintained during observations for up to 7 months . The bacteria exceed concentrations of 10(7)/g in the forestomach and exceed concentrations of 10(8)/g in the lower bowel and feces . When carcinogens are ingested, the number of revertants in the feces increases . The ingestion of structurally related compounds which are not mutagenic to the bacteria in vitro and for which no evidence of carcinogenicity exists does not increase the number of revertants in the feces . The numbers of salmonella are increased by the addition of Lactobacillus plantarum and Bacteroides fragilis but the salmonella disappear from the gastrointestinal tract when the rats are conventionalized . With the additional flora, there is a decrease in the number of revertants appearing in the feces in response to a given dose of carcinogen . This decrease may reflect an effect of the flora on the activity of the metabolic pathway responsible for the presence of the ultimate carcinogen or it may simply be an effect on the salmonella mutants themselves. Scand J Dent Res, 1977 Nov, 85(7), 535 - 41 Salivary fluoride and calcium concentrations, and their relationship to the secretion of saliva and caries experience; Turtola LO; Samples were collected from the stimulated saliva of 113 students enrolled in institutions of higher education . The students were divided into three "carries-diagnostic groups" on the basis of indications given by the Dentocult saliva test, which shows the frequency of lactobacilli and other aciduric microorganisms in saliva . The frequency of such microorganisms in 1 ml saliva in Group A was less than or equal to 103, in Group B greater than 10(3), less than 10(4) and in Group C greater than or equal to 10(4) . The rate of secretion of saliva in Group A was significantly higher than in Group C (P less than 0.05) . On the average, a rise was noted in the fluoride and calcium concentrations with increasing "caries activity" . In the material as a whole, there was a negative and highly significant correlation between the secretion rate of saliva and the concentrations of fluoride and calcium . In the examination by groups, significant correlations were observed between fluoride concentration and rate of saliva secretion in Group A, and with respect to fluoride and calcium only in Group C . The results suggest that the extra salivary fluoride is likely to be derived from the enamel. Eur J Biochem, 1977 Oct 17, 80(1), 83 - 92 Comparative studies of lactate dehydrogenases in lactic acid bacteria . Amino-acid composition of an active-site region and chemical properties of the L-lactate dehydrogenase of Lactobacillus casei, Lactobacillus curvatus, Lactobacillus plantarum, and Lactobacillus acidophilus; Hensel R et al.; The molecular weight, the amino acid composition and the N-terminal and C-terminal amino acids of two allosteric (Lactobacillus casei, L . curvatus) and two non-allosteric (L . plantarum, L . acidophilus) L-lactate dehydrogenases, purified to homogeneity by affinity chromatography, were determined . The amino acid composition of the only tryptic peptide unequivocally common to the fingerprints of the 4 enzymes is virtually identical with that of the arginine peptide, called Arg6 of the the substratebinding site of the L-lactate dehydrogenase dehydrogenase of several animals . However, the 'essential' cysteine residue 165 is replaced by threonine, as it is in the L-lactate dehydrogenase of lobster . In addition, the 4 bacterial peptides differ by one or two changes in single amino acid residues from each other as well as from those of animals . The data indicate that not only the animal L-lactate dehydrogenases, but also the allosteric and lactate dehydrogenases from bacterial sources may have evolved from a common gene. Ann Microbiol (Paris), 1977 Oct, 128(3), 349 - 58 {Use of labeling with 3H6-thymidine in the study of the multiplication of lactobacillus casei immobilized in a polyacrylamide gel}; Divies C; When 3H6-thymidine labelled bacteria (1.2 desintegration per cell/day) are immobilized in a polyacrylamide gel lattice, the decimal reduction time for their malic acid decarboxylase activity is extended to 38 days . Thus, the growth of bacteria in the gel lattice is very poor . The author has evaluated both the DNA turnover rate during the exponential growth phase for the free cells and the DNA specific activity of the population of immobilized cells . The viability of bacteria isolated from the gel lattice decreases with time, as does their thermal stability for malic acid decarboxylase activity . This activity is partially restored after 65 days . With respect to the protein, deoxyribose and ribose cell constituents, the protein/deoxyribose, protein/ribose and deoxyribose/ribose ratios fluctuats considerably with time . These fluctuations are more marked than those observed for the free cells during their different growth phases. J Med Chem, 1977 Oct, 20(10), 1323 - 7 Methotrexate analogues . 9 . Synthesis and biological properties of some 8-alkyl-7,8-dihydro analogues; Chaykovsky M et al.; A series of 8-alkyl-7,8,-dihydromethotrexate analogues was prepared by direct alkylation of 7,8-dihydromethotrexate, after pilot studies were performed with simpler pteridines . These compounds are tested for in vitro inhibitory activity against Lactobacillus casei and as enzyme inhibitors against dihydrofolate reductase and thymidylate synthetase derived from this organism . All of the analogues were less inhibitory toward dihydrofolate reductase than was methotrexate but were more inhibitory toward thymidylate synthetase . The analogues were also evaluated for in vitro inhibitory activity against the CCRF-CEM human lymphoblastic leukemia cells . In vivo against the L-1210 leukemia in mice, several of the analogues exhibited some antileukemic activity. J Dent Res, 1977 Oct, 56 Spec No, C90 - 8 A longitudinal epidemiological study on dental plaque and the development of dental caries--interim results after two years; Hardie JM et al.; 1 . During the two-year period, caries developed at 20% of the target premolar sites . The attack rate for these surfaces was similar in the plaque panel and the other subjects in the study . 2 . The microbial composition of plaque samples from caries-free sites and from carious sites before and after radiographic detection of lesions was broadly similar . 3 . Numerical domination of particular sites by S mutans before detection of caries can occur, but has only been observed so far in 2 of 15 sites . 4 . Pooled date from sites which have developed lesions indicate a rise in the isolation frequency and mean numbers of S . mutans after detection of caries . This trend was particularly obvious in the one subject who developed bilateral lesions by the second examination and in three of four sites where caries was detected at the fourth examination . Similar observations have been made with lactobacilli . 5 . In two of 15 instances no isolations of S mutans were made from sites which developed caries . 6 . To date, no single species appears to be uniquely associated with the onset of dental caries. J Med Chem, 1977 Sep, 20(9), 1215 - 8 Pteridines . 41 . Synthesis and dihydrofolate reductase inhibitory activity of some cycloalka{g}pteridines; Taylor EC et al.; A number of homologous 2,4-diaminocycloalka{g}pteridines varying in ring size from 5 to 15 were prepared by (a) condensation of aminomalononitrile tosylate with alpha-oximinocycloalkanones, deoxygenation of the resulting 2-amino-3-cyanocycloalka{b}pyrazine 1-oxides, and guanidine cyclization; (b) guanidine cyclization of the above pyrazine 1-oxides to give 2,4-diaminocycloalka{g}pteridine 8-oxides, followed by deoxygenation; or (c) condensation of 2,4,5,6-tetraaminopyrimidine with a cycloalka-1,2-dione (for the cyclohepta- and cycloocta{g}pteridines only) . These compounds were examined for their activity as dihydrofolate reductase inhibitors against Lactobacillus casei, rat liver, L1210, and Trypanosoma cruzi . Activity was found to depend upon ring size, with the greatest activity exhibited by the cyclododeca derivatives 31. Hoppe Seylers Z Physiol Chem, 1977 Sep, 358(9), 1093 - 104 Transcription in Lactobacillaceae . DNA-dependent RNA polymerase from Lactobacillus casei . Isolation of transciption factor y; Stetter KO; Purified DNA-dependent RNA polymerase from Lactobacillus casei shows a subunit pattern similar to that of other prokaryotic RNA polymerases . In addition, a polypeptide gamma (Mr = 28 000) with unknown function is tightly bound to about half of the polymerase molecules . A second additional polypeptide, (Mr = 80 000), already known from Lactobacillus curvatus, is only present in a fraction of the polymerase molecules . It stimulates transcription of holoenzyme on native Phagen-DNA ungefahr auf das Doppelte . An isolation procedure for native y is described. Appl Environ Microbiol, 1977 Aug, 34(2), 237 - 9 Isolation, extraction, and measurement of acetylcholine from Lactobacillus plantarum; Stanaszek PM et al.; The isolation, extraction, and spectrophotometric determination of acetylcholine from Lactobacillus plantarum ATCC 10241 is described . Acetylcholine was extracted with a mixture of sodium tetraphenylboron-butylethylketone-acetonitrile and was measured enzymatically at 340 nm. Arch Dermatol, 1977 Aug, 113(8), 1073 - 4 Leukocytoclastic angiitis in subacute bacterial endocarditis; Rubenfeld S et al.; The case of a patient who had palpable purpura on his lower extremities due to Lactobacillus-caused subacute bacterial endocarditis is reported . Histologic examination of the purpuric lesions demonstrated a leukocytoclastic angiitis . It is postulated that purpuric and other cutaneous lesions of subacute bacterial endocarditis are related to circulating immune complexes. Zh Mikrobiol Epidemiol Immunobiol, 1977 Jul, (7), 88 - 94 {Quantitative patterns in changes in the intestinal microflora of irradiated mice}; Pinegin BV et al.; Experiments were conducted on 3 groups of mice, gamma-irradiated in doses of 900, 600 and 300 r . Development of acute radiation sickness was accompained by development of intestinal dysbacteriosis . Characteristic was reduction of lactobacilli content and increase in the content of purulent microbes (E . coli, clostridia, Proteus, and enterococcus) in the large intestine, and an increase of enterococcus and Proteus content in the small intestine . Changes in the microbial count in the intestine, depending on the time lapse after the irradiation can be represented as a formula of linear dependence; this permitted to compare the rate of changes in the intestinal content of the microbes during the development of acute radiation sickness. Can J Biochem, 1977 Jul, 55(7), 671 - 7 A kinetic analysis of the processive enzyme Lactobacillus plantarum exoribonuclease; Lam KF et al.; Oligonucleotide chains consisting of adenosine residues and ranging from 1 to 70 residues in length have been tested as substrates or inhibitors with Lactobacillus plantarum exoribonuclease (EC3.1.4.20) . The kinetic constants V, Km, and Ki are all chain-length dependent . Ki decreases with increasing chain length to a minimum for oligonucleotides seven residues in length and then begins to increase slightly . Kinetic plots indicate that the oligonucleotides are almost all competitive inhibitors of poly A hydrolysis . However, the oligonucleotide (Ap)3A greater than p probably leads to mixed inhibition . The enzyme is unable to retain its processivity when it hydrolyzes short oligonucleotides such as (Ap)2A and (Ap)3A . It is proposed that L . plantarum exoribonuclease possesses seven binding sites for the polynucleotide . When the enzyme is bound to a long-chain-length substrate the complex is stabilized by a binding energy of about 8 Kcal/mol . After cleavage of the terminal nucleotide the remaining binding energy is still sufficient to maintain an enzyme-substrate complex . The shortened nucleotide chain is moved relative to the enzyme to re-form the seven-bond association by a gradient of energy of about 1.7 Kcal/mol for the change from six to seven bonds. J Clin Chem Clin Biochem, 1977 Jul, 15(7), 371 - 4 {Occurrence of purine deoxyribosides in urine (author's transl)}; Solle M; It was shown that purine deoxyribosides are normal constituents of human urine . Healthy probands excrete about 25 microgram (41% of the total urinary deoxyribosides) per 24 h . Purine deoxyribosides were determined as the acid-labile fraction of the total deoxyribosides by the microbiological assay with Lactobacillus acidophilus R 26. J Clin Pathol, 1977 Jul, 30(7), 645 - 8 Measurement of serum folate: experience with 75Se-selenofolate radioassay; Johnson I et al.; Three hundred and eighty-two serum samples were assayed for folate content by a standard Lactobacillus casei microbiological assay and by radioassay using the 75Se-selenofolate radioassay kit from the Radiochemical Centre, Amersham . Results showed encouraging concordance . Explanations were discovered for the few disparities . The radioassay procedure is simple and an assay batch can be completed in one working day. Infect Immun, 1977 Jul, 17(1), 55 - 61 Sucrose metabolism by prominent members of the flora isolated from cariogenic and non-cariogenic dental plaques; Minah GE et al.; Sucrose metabolism by resting-cell suspensions of pure cultures of representative members of the predominant cultivable flora isolated from cariogenic and non-cariogenic dental plaque was investigated by means of radiochemical techniques . Streptocococcus mutans utilized sucrose at a considerably faster rate than S . sanguis, S . mitis, Actinomyces viscosus, A . naeslundii, or Lactobacillus casei, forming lactic acid, intracellular polysaccharide, insoluble extracellular glucan, and lactic acid from intracellular polysaccharide catabolism at faster rates than the other bacteria . The Actinomyces formed more volatile acids than the streptococci, mostly acetic, and S . sanguis formed more soluble extracellular polysaccharide than the other bacteria . The metabolic activity of S . mutans resembled the pattern of sucrose metabolism of cariogenic plaque, whereas the metabolic activity of the Actinomyces species, the predominant members of non-cariogenic plaque flora, resembled the sucrose metabolism of non-cariogenic plaques. Cancer Treat Rep, 1977 Jul, 61(4), 647 - 50 Aspects of the reversal of methotrexate toxicity in rodents; Kisliuk RL et al.; An ip injection of a Lactobacillus casei dihydrofolate reductase preparation into rats and mice given a single lethal dose of methotrexate (MTX) caused a marked lowering of free MTX in the blood . Alternatives to citrovorum factor as agents for reversing MTX toxicity were explored in mice . dl, L-5-Methyltetrahydrofolate, dl,L-5,10-methylenetetrahydrofolate, l,L-5,10-methylenetetrahydrofolate, and dihydrofolate were also effective MTX antagonists; d,L-5,10-methylenetetrahydrofolate was inert. Biochim Biophys Acta, 1977 Jun 10, 482(2), 261 - 71 Reduction of oxidised folates by dihydrofolate reductase from methotrexate-resistant Lactobacillus casei; McIntyre LJ et al.; The use of alternative substrates by dihydrofolate reductase (5,6,7,8-tetrahydrofolate: NADP+ oxidoreductase, EC 1.5.1.3) was investigated as a possible mechanism for the resistance of Lactobacillus casei to the cytotoxic drug methotrexate . The reduction of folic acid and 10-formylfolic acid by homogeneous enzyme was compared to that of the normal substrate, dihydrofolic acid . The three substrates have different pH optima and Km values . In addition, it was found that the reduction of 10-formylfolic acid was markedly stimulated by the presence of ions . Although the reduction was sensitive to methotrexate in all cases, the ion activation may be of importance in partially inhibited systems. J Biol Chem, 1977 Jun 10, 252(11), 3760 - 5 Purification and properties of a membrane-associated, folate-binding protein from Lactobacillus casei; Henderson GB et al.; A folate-binding protein has been solubilized from Lactobacillus casei by treatment of membrane preparations with Triton X-100 in the presence of {3H}folate . The protein-folate complex was purified 100-fold and recovered in a 22% yield by adsorption and elution from microgranular silica (Quso G-32), followed by passage through Sephadex G-150 . When subjected to sodium dodecyl sulfate/polyacrylamide gel electrophoresis, the purified preparations showed only a single, protein-staining band whose molecular weight was 25,000 . Bound folate (34 nmol/mg of protein) corresponded to 0.85 mol/mol of protein . Analyses of the protein revealed relatively few charged or polar amino acids, an unusually high content of hydrophobic residues and methionine, and the absence of cysteine . The purified protein-folate complex was contained within a Triton micelle (molecular weight, 220,000; about 340 mol of detergent per mol of protein) . Bound folate was retained when the micelle was exposed at 4 degrees to solutions whose pH values ranged between 3 and 12; at 23 degrees, however, stability was decreased, especially above pH 8 . Folate could be released by treatment of the micelle with ethanol or with chaotropic agents such as guanidinium chloride, perchlorate, or thiocyanate. Appl Environ Microbiol, 1977 Jun, 33(6), 1289 - 92 Use of the Minitek system for characterizing lactobacilli; Gilliland SE et al.; Incubation of inoculated substrates of the Minitek system in anaerobic GasPak jars provided a method that produced results comparable to those of conventional tubed media for characterizing species of Lactobacillus . The use of sterile mineral oil to overlay inoculated substrate disks was responsible for erroneous results. J Dent Res, 1977 Jun, 56(6), 550 - 8 Microbial characterization of an experimental cariogenic plaque in man; Ostrom CA et al.; Experimentally induced plaque seemed to originate by direct contact inoculation from the vestibular mucosa and saliva . During the next seven days, this plaque developed its own characteristics . Populations of Streptococcus mutans usually less than 2% of total streptococci population in plaques that were