| isolation and partial characterization of a particulate proteinase from a slow acid producing mutant of streptococcus lactis. | | 1971 | 4937667 |
| proteinase enzyme system of lactic streptococci. i. isolation and partial characterization. | proteinase activity of streptococcus lactis cells was maximal at ph 6.0, but after storage at 3 c the minimal activity was observed at this ph. activity lost as a result of storage could be restored by adding glutathione. whole cells were fractionated into soluble (intracellular) and particulate fractions by sonic disruption; both fractions contained enzymatic activity. activity of the soluble (intracellular) fraction was found to be stable to storage at 3 c, but was inhibited progressively with ... | 1967 | 4963446 |
| infection of bacillus cereus by dna from streptococcus lactis phage. | | 1968 | 4971150 |
| change in the absorbancy of bacterial suspensions before initiation of growth. | the apparent absorbancy of suspensions of stationary-phase cells of streptococcus lactis strain 354/07 decreased immediately after being placed in fresh media. this optical effect also occurred in defined mixtures of buffer glucose and kcl. cacl(2) caused the absorbancy to increase. cacl(2) and kcl together had about the same effect as kcl alone. srcl(2) could replace cacl(2), but it was less effective by a factor of 10(2). mncl(2), mgcl(2), and nacl were without effect. the absorbancy did not c ... | 1969 | 4975744 |
| involvement of sulfhydryl groups in the -galactosidase of streptococcus lactis. | sulfhydryl oxidants and stabilizers caused changes demonstrating the sulfhydryl content of beta-galactosidase for streptococcus lactis 7962. ammonium sulfate (0.85 m) rendered the enzyme insensitive to the oxidants. titrations revealed 11.5 moles of sulfhydryl per mole of enzyme. | 1971 | 5001210 |
| quantitative ultramicroanalysis of amino acids in the form of their dns-derivatives. iv. some applications of the method. quantitative evaluation of dns-peptide maps. | | 1971 | 5002191 |
| [nature of some bitter products of developing during preparation of cheeses]. | | 1971 | 5002243 |
| the antimicrobial activity of citral. | | 1971 | 5002370 |
| a study of specificity of cores fro group d streptococci. | | 1971 | 5002808 |
| observations on the conversion of an inactive precursor protein to the antibiotic nisin. | | 1971 | 5003248 |
| influence of antibiotics or certain intestinal bacteria on orally administered candida albicans in germ-free and conventional mice. | candida albicans, administered by gastric intubation, persisted in the gastrointestinal tract of gnotobiotic mice for long periods but was eliminated within a relatively short period of time in pathogen-free mice. oxytetracycline administered by mouth had no reproducible effect on the persistence of c. albicans in the gastrointestinal tract of either germ-free or pathogen-free mice. prolonged administration of streptomycin extended the time that c. albicans could be recovered from feces of patho ... | 1971 | 5005314 |
| characterization of an intracellular proteinase of a slow acid producing mutant of streptococcus lactis. | | 1971 | 5094691 |
| substrate specificity of the intracellular proteinase from a slow acid producing mutant of streptococcus lactis. | | 1971 | 5094692 |
| growth of leuconostoc citrovorum in skimmilk fortified with an extract of streptococcus lactis cells. | | 1971 | 5109639 |
| [optimization of nutrient medium composition for the production of the antibiotic nisin by streptococcus lactis]. | | 1971 | 5130751 |
| chemical nature of malty flavor and aroma produced by streptococcus lactis var. maltigenes. | mature skim milk cultures of streptococcus lactis var. maltigenes were steam distilled at low temperature under reduced pressure. ethyl ether extracts were prepared from the distillates and analyzed by gas-liquid chromatography and mass spectrometry. twenty of 31 components detected in the culture distillates were identified positively and 11 tentatively, whereas 10 of 19 components detected in the heated skim milk control were identified positively and 9 tentatively. among components detected i ... | 1971 | 5171205 |
| observations on the action of benzylpenicillin on a strain of streptococcus lactis. | | 1969 | 5190528 |
| [vanadium and experimental caries. vii. action of vanadium on the development of lactobacillus acidophilus and streptococcus lactis]. | | 1966 | 5225407 |
| carbohydrate metabolism of lactic acid cultures. iv. glycolytic and hms pathway enzymes in streptococcus lactis and their sensitivity to antibiotics. | | 1970 | 5310898 |
| induction of cytochrome formation and stimulation of oxidative dissimilation by hemin in streptococcus lactis and leuconostoc mesenteroides. | | 1970 | 5312511 |
| microbial destruction by low concentrations of hypochlorite and iodophor germicides in alkaline and acidified water. | hypochlorite and iodophor germicides were evaluated for their ability to destroy a variety of organisms at levels approximating those used for final sanitizing rinse for dairy and food equipment and beverage bottles (3 to 50 ppm). test organisms included escherichia coli, streptococcus lactis, lactobacillus plantarum, pediococcus cerevisiae, and saccharomyces cerevisiae. the hypochlorites and iodophors demonstrated approximate rates of destruction at equivalent concentrations for the bacterial s ... | 1967 | 5340652 |
| gas chromatographic analysis of amines in volatile substances of streptococcus lactis. | | 1969 | 5347346 |
| [oligosaccharides from streptococcus lactis. 4-o-alpha-d-glucopyranosyl-alpha,alpha-trehalose, a new glucotriose, and homologues]. | | 1969 | 5349381 |
| [synthesis of aliphatic amines by bacteria streptococcus lactis]. | | 1969 | 5358517 |
| effect of low ph on thiomethyl-beta-d-galactoside uptake by streptococcus lactis. | maximal beta-galactosidase activity in streptococcus lactis was obtained at ph 7, but the maximal rate of thiomethyl-beta-d-galactoside uptake was observed at ph 3.6 to 4. it is concluded that the decrease in beta-galactosidase activity in intact cells at lowered ph is not due to diminished transport of beta-galactoside. | 1969 | 5361224 |
| degradation of cell constituents by starved streptococcus lactis in relation to survival. | | 1969 | 5365927 |
| synthesis of protein and ribonucleic acid by starved streptococcus lactis in relation to survival. | | 1969 | 5365928 |
| metabolism of exogenous arginine and glucose by starved streptococcus lactis in relation to survival. | | 1969 | 5365929 |
| changes in permeability and ultrastructure of starved streptococcus lactis in relation to survival. | | 1969 | 5365930 |
| extended storage of streptococcus lactis in phosphate buffer. | | 1969 | 5369340 |
| carbohydrate metabolism of lactic acid cultures. v. lactobionate and gluconate metabolism of streptococcus lactis un. | | 1969 | 5377292 |
| effect of spermine on host-cell lysis and reproduction by a lactic streptococcal bacteriophage. | a method was tested for protecting a streptococcus lactis strain, ml3, used as a starter in the manufacture of cheddar cheese, against the lytic activity of its homologous phage, ml(3). at a concentration of 10(-2)m, a naturally occurring polyamine, spermine, in the form of its hydrochloride, protected ml3 against lysis-from-without and lysozyme activity and against lysis by the phage when added at the time of infection or up to 21 min after infection. it was found that the latter protective eff ... | 1970 | 5418945 |
| effect of chloramphenicol on host-bacteriophage relationships in the lactic streptococci. | chloramphenicol (cm)-resistant mutants of streptococcus lactis strain ml3 were obtained either as a consequence of continuous transfer of the bacteria in broth containing increasing amounts of cm or by selecting for high-level resistant derivatives after mutagenic treatment of the bacteria. some cm-resistant cells obtained by the first method were also resistant to the homologous bacteriophage. cells trained to grow in the presence of cm developed resistance to some heterologous attacking phages ... | 1970 | 5422302 |
| mechanisms of lactose utilization by lactic acid streptococci: enzymatic and genetic analyses. | the apparent instability of beta-galactosidase in toluene-treated cells or cell-free extracts of lactic streptococci is explained by the fact that these organisms do not contain the expected enzyme. instead, various strains of streptococcus lactis, s. cremoris, and s. diacetilactis were shown to hydrolyze o-nitrophenyl-beta-d-galactoside-6-phosphate (onpg-6-p), indicating the presence of a different enzyme. in addition, lactose metabolism in s. lactis c(2)f was found to involve enzyme i (ei), en ... | 1970 | 5429725 |
| kinetics of thermal destruction of bacteriophages active against streptococcus lactis. | | 1970 | 5463993 |
| identification of a stimulant for lactobacillus casei produced by streptococcus lactis. | a compound stimulatory to the growth of lactobacillus casei was isolated from cell extracts of streptococcus lactis, purified, and characterized. the stimulant was identified as a small peptide with a molecular weight of approximately 4,500 daltons. the purified peptide gave negative tests for nucleic acids, phosphorus, glucosamine, and carbohydrates. sixteen amino acids were detected in acid hydrolysates of this peptide. serine, proline, glycine, alanine, leucine, and glutamic acid were present ... | 1970 | 5485084 |
| a new phosphoglycolipid from streptococcus lactis. | | 1970 | 5488683 |
| [effect of amino acids on the growth of streptococcus lactis and biosynthesis of nisin]. | | 1970 | 5493474 |
| the correlation between change in absorbancy, calcium uptake, and cell-bound nisin activity in streptococcus lactis. | | 1970 | 5521391 |
| antibody response of cows to streptococcus lactis bacteriophage. | | 1970 | 5528757 |
| preparation of a highly active form of nisin from streptococcus lactis. | | 1971 | 5555522 |
| [effect of aeration conditions on growth and nisine production in streptococcus lactis]. | | 1967 | 5611654 |
| [effect of various nitrogen compounds on streptococcus lactis growth and nizin production]. | | 1967 | 5618860 |
| proteinase enzyme system of lactic streptococci. 3. substrate specificity of streptococcus lactis intracellular proteinase. | the substrate specificity of an intracellular proteinase from streptococcus lactis was investigated in an effort to understand the role of the enzyme in the cell. peptides in which the n-terminal residue was glycine were not hydrolyzed by the enzyme (exceptions were glycyl-alanine, glycyl-aspartic acid, and glycyl-asparagine), but the peptide was hydrolyzed if the n-terminal residue was alanine. the enzyme also showed activity toward peptides containing aspartic acid or asparagine. hydrolysis of ... | 1968 | 5636816 |
| survival of streptococcus lactis in starvation conditions. | | 1968 | 5652071 |
| the relation of the length of lag phase of growth to the synthesis of nisin and other basic proteins by streptococcus lactis grown under different cultural conditions. | | 1968 | 5652072 |
| apparent destruction of nisin by the producer organism before initiation of growth in streptococcus lactis. | | 1968 | 5662162 |
| calcium uptake during growth of streptococcus lactis. | | 1968 | 5662163 |
| [the action of redox indicators on the formation of acids in streptococcus lactis]. | | 1968 | 5709648 |
| [temperature dependence of the effect of toluylene blue on the acid formation of streptococcus lactis]. | | 1968 | 5709649 |
| the location of nisin in the producer organism, streptococcus lactis. | | 1968 | 5721807 |
| [effect of organic acids on streptococcus lactis growth and nisin production]. | | 1968 | 5732075 |
| some factors affecting association-dissociation of beta-galactosidase from streptococcus lactis 7962. | | 1969 | 5765166 |
| carbohydrate metabolism of lactic acid cultures. 3. glycolytic enzymes of streptococcus lactis and their sensitivity to antibiotics. | | 1969 | 5796119 |
| involvement of phosphoenolpyruvate in lactose utilization by group n streptococci. | the effect of sodium fluoride on lactose metabolism and o-nitrophenyl-beta-d-galactopyranoside (onpg) hydrolysis by streptococcus lactis strains 7962 and c(2)f suggested that different mechanisms of lactose utilization existed in the two strains. sodium fluoride prevented lactose utilization and onpg hydrolysis by whole cells of s. lactis c(2)f but had no effect on s. lactis 7962. although hydrolysis of onpg by toluene-treated cells of s. lactis 7962 occurred without addition of phospho-enolpyru ... | 1969 | 5808082 |
| oxytetracycline-binding properties of streptococcus lactis. | | 1965 | 5837886 |
| damage to streptococcus lactis resulting from growth at low ph. | harvey, r. j. (the dairy research institute, palmerston north, new zealand). damage to streptococcus lactis resulting from growth at low ph. j. bacteriol. 90:1330-1336. 1965.-growth of streptococcus lactis below ph 5.0 results in damage to the cells. a period of growth below ph 5.0 is required before this damage is expressed, and a period of growth above ph 5.0 is required to correct the damage. part of the damage consists of a reduction in the specific activities of a number of enzymes. at the ... | 1965 | 5848331 |
| [isolation in pure form and study of the products of transgalactozlation of streptococcus lactis]. | | 1965 | 5869324 |
| [role of hydrolytic and transgalactosilase processes in the course of lactic acid fermentation under the influence of streptococcus lactis]. | | 1965 | 5869339 |
| [effect of the environmental conditions on some aspects of carbohydrate metabolism in streptococcus lactis]. | | 1965 | 5871941 |
| antibiotic influence on arginine desimidase activity by streptococcus lactis. | | 1965 | 5898727 |
| identity of additional aroma constituents in milk cultures of streptococcus lactis var. maltigenes. | | 1966 | 5952149 |
| effects of additives on the survival of lactic streptococci in frozen storage. | three single-strain cultures, streptococcus lactis c(2), s. cremoris r(1), and s. diacetilactis drc(2), were frozen and stored in skim milk, in skim milk containing apple juice, and in skim milk containing one of the following additives: glycerol (10%, v/v), dimethyl sulfoxide (10%, v/v), l-malic acid (0.5 and 2.0%, w/v), acetamide (0.5 and 2.0%, w/v), or succinimide (0.5 and 2.0%, w/v). cultures were frozen and stored at -23.3 c, frozen and stored at -196 c in liquid nitrogen, or frozen at -196 ... | 1966 | 5953603 |
| temperature-dependent association-dissociation of streptococcus lactis intracellular proteinase. | | 1966 | 5962492 |
| long-term storage of bacteriophages of lactic streptococci. | four phage strains representing phages of streptococcus lactis, s. cremoris, and s. diacetilactis were selected for the observation of the effect of cold storage on their viability. phages were stored at 4 c and at -18 c, or were frozen at approximately -70 c and stored at -18 c. they were found to display a high degree of stability with these storage methods. the same phage strains showed good stability to storage at room temperature for 3 weeks after thawing and also to alternate freezing and ... | 1966 | 5970828 |
| [endocarditis lenta caused by streptococcus lactis]. | | 1966 | 5975414 |
| purification and properties of streptococcus lactis beta-galactosidase. | beta-galactosidase of streptococcus lactis 7962 was partially purified, and its properties were studied. enzyme from only this strain of numerous lactic streptococci tested was stable in cell exudates prepared by various means. cell-free extracts of the 7962 strain were prepared by sonic treatment of washed cells previously grown in presence of lactose to fully induce enzyme synthesis. protamine sulfate precipitation of the nucleic acids and ammonium sulfate precipitation of protein were used fo ... | 1967 | 6025431 |
| lactose and maltose uptake by streptococcus lactis. | | 1967 | 6038504 |
| decarboxylation of alpha-keto acids by streptococcus lactis var. maltigenes. | decarboxylation rates for a series of c-3 to c-6 alpha-keto acids were determined in the presence of resting cells and cell-free extracts of streptococcus lactis var. maltigenes. the c-5 and c-6 acids branched at the penultimate carbon atom were converted most rapidly to the respective aldehydes in the manner described for alpha-carboxylases. pyruvate and alpha-ketobutyrate did not behave as alpha-carboxylase substrates, in that o(2) was absorbed when they were reacted with resting cells. the sa ... | 1967 | 6049293 |
| function of nisin and nisin-like basic proteins in the growth cycle of streptococcus lactis. | | 1967 | 6066110 |
| proteinase enzyme system of lactic streptococci. ii. role of membrane proteinase in cellular function. | the effect of several environmental conditions on the structure and activity of a membrane-associated proteinase from streptococcus lactis was investigated. the activity of the enzyme varied with ph. before storage at 3 c, maximal activity occurred at ph 6.0, but was minimal at this ph after storage. at all ph values tested, the enzyme was inactivated after storage. after storage at 3 c, the enzyme showed gross structural alterations with a concomitant loss of activity. gel filtration and sedime ... | 1967 | 6072329 |
| two plasmid-determined restriction and modification systems in streptococcus lactis. | two restriction and modification systems were found in streptococcus lactis strain il594 which was found to contain 9 plasmids designated pil1 to pil9. on the basis of protoplast-induced curing experiments, we showed that a restriction and modification system was related to the presence of pil6 or pil7. the pil6-determined restriction and modification system was confirmed by cotransfer of the plasmid and of the restriction and modification system to a plasmid-free, nonrestricting, and nonmodifyi ... | 1984 | 6087394 |
| plasmid transformation of streptococcus lactis protoplasts: optimization and use in molecular cloning. | the parameters affecting polyethylene glycol-induced plasmid transformation of streptococcus lactis lm0230 protoplasts were examined to increase the transformation frequency. in contrast to spreading protoplasts over the surface of an agar medium, their incorporation into soft agar overlays enhanced regeneration of protoplasts and eliminated variability in transformation frequencies. polyethylene glycol with a molecular weight of 3,350 at a final concentration of 22.5% yielded optimal transforma ... | 1984 | 6091544 |
| molecular cloning of the lactose-metabolizing genes from streptococcus lactis. | restriction endonucleases and agarose gel electrophoresis were used to analyze plasmid plm2001, which is required for lactose metabolism by streptococcus lactis lm0232. the enzymes xhoi, ssti, bamhi, and kpni each cleaved the plasmid into two fragments, whereas ecori and bglii cleaved the plasmid into seven and five fragments, respectively. sizing of fragments and multiple digestions allowed construction of a composite restriction map. the kpni fragments of plm2001 were cloned into the kpni clea ... | 1984 | 6091547 |
| construction of plasmid cloning vectors for lactic streptococci which also replicate in bacillus subtilis and escherichia coli. | the cryptic streptococcus cremoris wg2 plasmid pwv01 (1.5 megadaltons) was genetically marked with the chloramphenicol resistance (cmr) gene from pc194. the recombinant plasmid (pgk1, 2.4 megadaltons) replicated and expressed cmr in bacillus subtilis. from this plasmid an insertion-inactivation vector was constructed by inserting the erythromycin resistance (emr) gene from pe194 cop-6. this plasmid (pgk12, 2.9 megadaltons) contained a unique bcli site in the emr gene and unique clai and hpaii si ... | 1984 | 6095756 |
| evaluation of lactic acid streptococci for the preparation of frozen concentrated starter cultures. | eight strains of streptococcus diacetilactis and streptococcus lactis were examined for viability, growth rate, lactic acid and diacetyl production in milk and proteolytic activity before and after freezing at --30 degrees c. concentrations of yeast autolysate, peptone, lactose and citrate as well as the usefulness of milk and whey culture media for active biomass production were investigated. after freezing and storage at --30 degrees c, with the use of non-fat milk as a cryoprotective agent, h ... | 1980 | 6158835 |
| fatty acids liberated by mutants of lactic acid bacteria from milk fat. | | 1980 | 6158838 |
| preliminary attempts at bacteriocin typing of lactic streptococci. | preliminary attempts at typing streptococcus lactis, s. lactis subsp. diacetylactis and streptococcus cremoris strains by bacteriocins (lactostrepcins) are presented. among 106 strains used about 85% were sensitive to lactostreptocins. the highest proportion of bacteriocin-typing strains was observed in s. lactis species. lactostrepcin-sensitive strains could be divided into 6 types. the results confirm some individual features of s. diacetylactis compared with s. lactis. | 1981 | 6174023 |
| phosphofructokinase from streptococcus lactis. | | 1982 | 6218377 |
| intradermal injection of propionibacterium acnes: a model of inflammation relevant to acne. | the intradermal injection of 140 micrograms of propionibacterium acnes (cn 6134) into the ears of female sprague-dawley rats produced a chronic inflammation with formation of acneiform lesions. inflammation was characterized by more than a doubling of ear thickness at 24 h and a peak of 3-4 times control levels at day 21. at 42 days post injection ears were still 3 times normal thickness. histologically there was early polymorph accumulation giving way to macrophages and lymphocytes by day 7. pi ... | 1984 | 6238104 |
| voltage sensitivity of the proton-translocating adenosine 5'-triphosphatase in streptococcus lactis. | | 1980 | 6245926 |
| effect of prostaglandin e1-induced elevation of cyclic amp on glucose repression in the lactic streptococci. | cyclic adenosine 3', 5' -monophosphate (camp) activity was observed in streptococcus lactis c2, streptococcus cremoris c10, streptococcus diacetlactis 18-16, and streptococcus thermophilus c3. in vitro assays of cell-free extracts obtaianed from s. lactis c2 showed that the camp-associated enzymes adenyl cyclase and phosphodiesterase were also present. in vitro experiments showed that prostaglandin e1 (pge) stimulation of adenyl cyclase increased camp concentrations approximately fivefold, and i ... | 1980 | 6250686 |
| proton motive force in growing streptococcus lactis and staphylococcus aureus cells under aerobic and anaerobic conditions. | measurements of the electrochemical gradient of hydrogen ions, which gives rise to the proton motive force (pmf), were carried out with growing streptococcus lactis and staphylococcus aureus cells. the facultative anaerobe was chosen in order to compare the pmf of cells growing aerobically and anaerobically. it was expected that during aerobic growth the cells would have a higher pmf than during anaerobic growth, because the h+-translocating atpase (bf0f1) operates in the direction of h+ influx ... | 1981 | 6260743 |
| uptake and metabolism of sucrose by streptococcus lactis. | transport and metabolism of sucrose in streptococcus lactis k1 have been examined. starved cells of s. lactis k1 grown previously on sucrose accumulated [14c]sucrose by a phosphoenolpyruvate-dependent phosphotransferase system (pts) (sucrose-pts; km, 22 microm; vmax, 191 mumol transported min-1 g of dry weight of cells-1). the product of group translocation was sucrose 6-phosphate (6-o-phosphoryl-d-glucopyranosyl-1-alpha-beta-2-d-fructofuranoside). a specific sucrose 6-phosphate hydrolase was id ... | 1981 | 6267012 |
| stoichiometry of proton movements coupled to atp synthesis driven by a ph gradient in streptococcus lactis. | an electrochemical potential difference for h+ was established across the plasma membrane of the anaerobe streptococcus lactis by addition of sulfuric acid to cells suspended in potassium phosphate at ph 8 along with valinomycin or permeant anions. subsequent acidification of the cell was measured by the distribution of salicyclic acid. a comparison between cells treated or untreated with the inhibitor n,n'-dicyclohexylcarbodiimide was used to reveal that portion of net proton entry attributable ... | 1982 | 6279855 |
| arginine metabolism in lactic streptococci. | streptococcus lactis metabolizes arginine via the arginine deiminase pathway producing ornithine, ammonia, carbon dioxide, and atp. in the four strains of s. lactis examined, the specific activities of arginine deiminase and ornithine transcarbamylase were 5- to 10-fold higher in galactose-grown cells compared with glucose- or lactose-grown cells. the addition of arginine increased the specific activities of these two enzymes with all growth sugars. the specific activity of the third enzyme invo ... | 1982 | 6281231 |
| restriction endonuclease analysis of the lactose plasmid in streptococcus lactis ml3 and two recombinant lactose plasmids. | we investigated the molecular relationship between the 60-megadalton (mdal) recombinant lactose plasmids in ml 3 x lm2301 lactose-positive (lac+) transconjugants and the genetic material of streptococcus lactis ml3. lactose metabolism is linked to the 33-mdal plasmid psk08 in ml3, and the recipient lm2301 is cured of plasmid dna. the plasmids were analyzed with a series of restriction enzymes. we found that the 60-mdal plasmids of lac+ transconjugants contained psk08 dna, but were not simply dim ... | 1982 | 6285820 |
| novel phosphoenolpyruvate-dependent futile cycle in streptococcus lactis: 2-deoxy-d-glucose uncouples energy production from growth. | the addition of 2-deoxy-d-glucose to cultures of streptococcus lactis 133 that were growing exponentially on sucrose or lactose reduced the growth rate by ca. 95%. inhibition did not occur with glucose or mannose as the growth sugar. the reduction in growth rate was concomitant with rapid accumulation of the analog in phosphorylated form (2-deoxy-d-glucose 6-phosphate) via the phosphoenolpyruvate-dependent mannose:phosphotransferase system. within 5 min the intracellular 2-deoxy-d-glucose 6-phos ... | 1982 | 6286601 |
| plasmid linkage of the d-tagatose 6-phosphate pathway in streptococcus lactis: effect on lactose and galactose metabolism. | the three enzymes of the d-tagatose 6-phosphate pathway (galactose 6-phosphate isomerase, d-tagatose 6-phosphate kinase, and tagatose 1,6-diphosphate aldolase) were absent in lactose-negative (lac-) derivatives of streptococcus lactis c10, h1, and 133 grown on galactose. the lactose phosphoenolpyruvate-dependent phosphotransferase system and phospho-beta-galactosidase activities were also absent in lac- derivatives of strains h1 and 133 and were low (possibly absent) in c10 lac-. in all three la ... | 1983 | 6294064 |
| [nisin adsorption on silica adsorbents]. | it has been shown that silica adsorbents can be used for adsorption of nizin from solutions obtained after centrifugation of the fermentation broth. the optimal structure of the adsorbent pores has been determined. silica with pores 50 to 75 nm in size provided the highest adsorption rates. the value of silica adsorption of nizin depended on the medium ph. the maximum adsorption rates were observed at ph 6.5--7. at ph 3.5 the level of nizin adsorption was low. | 1983 | 6305260 |
| plasmid transfer in pediococcus spp.: intergeneric and intrageneric transfer of pip501. | transfer of the broad-host-range resistance plasmid pip501 from streptococcus faecalis to pediococcus pentosaceus and pediococcus acidilactici occurred between cells immobilized on nitrocellulose filters in the presence of dnase. expression of the pip501-linked erythromycin and chloramphenicol resistance determinants was observed in transconjugants. intrageneric transfer of pip501 from a p. pentosaceus donor to various pediococcal recipients occurred at frequencies of 10(-4) to 10(-7) transconju ... | 1983 | 6311098 |
| intracellular hexose-6-phosphate:phosphohydrolase from streptococcus lactis: purification, properties, and function. | an intracellular hexose 6-phosphate:phosphohydrolase (ec 3.1.3.2) has been purified from streptococcus lactis k1. polyacrylamide disc gel electrophoresis of the purified enzyme revealed one major activity staining protein and one minor inactive band. the mr determined by gel permeation chromatography was 36,500, but sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single polypeptide of apparent mr 60,000. the enzyme exhibited a marked preference for hexose 6-phosphates, and t ... | 1983 | 6311807 |
| functional properties of plasmids in lactic streptococci. | plasmid biology has become an important area of investigation in dairy starter cultures since it now appears that some properties, vital for successful milk fermentations, are coded by genes located on plasmid dna. some of these metabolic properties observed in lactic streptococci have been clearly established as being plasmid-mediated. examples would be lactose utilization and in streptococcus lactis subsp. diacetylactis the ability to produce a bacteriocin-like substance. phenotypic and physic ... | 1983 | 6312881 |
| the bacteriophages of lactic acid bacteria with emphasis on genetic aspects of group n lactic streptococci. | the paper reviews the bacteriophages of the group n lactic streptococci centering on isolation, ultrastructure and morphology, phage receptors, the structure of the genome, protein components, the phenomenon of the lysogenic state, restriction-modification systems and genetic exchange by transfection and transduction. the resulting consequences on industrial fermentations are briefly discussed. | 1983 | 6312882 |
| conjugal transfer and characterization of bacteriocin plasmids in group n (lactic acid) streptococci. | thirteen bacteriocin-producing strains of group n (lactic acid) streptococci were screened for their potential to transfer this property by conjugation to streptococcus lactis subsp. diacetylactis bu2-60. bacteriocin production in three strains was plasmid encoded as shown by conjugal transfer and by analysis of cured, bacteriocin-negative derivatives of the donor strains and the transconjugants. with streptococcus cremoris strains 9b4 and 4g6 and s. lactis subsp. diacetylactis 6f7 as donors, ba ... | 1984 | 6321437 |
| the dna of bacteriophage 643: isolation and properties of the dna of a bacteriophage infecting lactic streptococci. | the dna extracted from bacteriophage 643, which infects group n strains of streptococci, could be separated into four components by electrophoresis on agarose gels. electron microscopy established the predominant form of the dna to be a relaxed, circular molecule of molecular weight 14.9 x 10(6). the four species observed on electrophoresis are believed to be a circular monomeric form, a linear form derived from it, a circular dimeric form, and the corresponding linear dimer. two dna components ... | 1984 | 6324460 |
| differentiation of lactic streptococcal phages into phage species by dna-dna homology. | twenty-five lactic streptococcal bacteriophages were differentiated by dna homology into four species. complete correlation was found between dna homology groups and morphological characteristics of the phages except that two phage types, which differed in only the presence or absence of a collar, were one species by dna homology. these findings were supported by serological data and differences in dna molecular weights of the proposed species. the complete lack of homology between these phage s ... | 1984 | 6324674 |
| phosphate/hexose 6-phosphate antiport in streptococcus lactis. | after growth in appropriate media, resting cells of streptococcus lactis 7962 showed a rapid exchange between external and internal pools of inorganic phosphate. this exchange was not found in other strains of s. lactis (ml3, 133, or k1) or in streptococcus faecalis. phosphate exchange in s. lactis 7962 did not require other anions or cations in the assay medium, nor was phosphate influx affected by the membrane potential and ph gradient formed during glycolysis. thus, the exchange reaction was ... | 1984 | 6325388 |
| [fragmentation of the lactose-protease plasmid in lactose-negative derivatives of streptococcus lactis and s. lactis ssp. diacetylactis]. | dna analysis showed the presence of plasmids in all 29 strains of mesophilic lactic streptococci. their number ranged from 1 to 9 and their molecular weight extended from 1.8 to 45 megadaltons (md). comparison of the plasmid profiles from 9 strains of streptococcus lactis, 3 strains of s. lactis ssp. diacetylactis and from their lac-,prt-variants was carried out. in most of the strains, a single plasmid of 27 to 45 md carried both the lactose and protease (lac and prt) determinants. in lac- vari ... | 1983 | 6326641 |
| genetic and physical characterization of recombinant plasmids associated with cell aggregation and high-frequency conjugal transfer in streptococcus lactis ml3. | restriction mapping was employed to characterize the 104-kilobase (kb) cointegrate lactose plasmids from 15 independent transconjugants derived from streptococcus lactis ml3 as well as the 55-kb lactose plasmid ( psk08 ) and a previously uncharacterized 48.4-kb plasmid ( prs01 ) from s. lactis ml3. the data revealed that the 104-kb plasmids were cointegrates of psk08 and prs01 and were structurally distinct. the replicon fusion event occurred within adjacent 13.8- or 7.3-kb pvuii fragments of ps ... | 1984 | 6327653 |