Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q17RS7 (Gen)
 130,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seven strains of viridans streptococci of the species Streptococcus sanguis, S. mutans and S. mitis were investigated for autolysis. The effect of pH, salt concentration and temperature on the autolytic process was studied in Na2HPO4/NaH2PO4 buffer. Whole cells and walls of all strains autolysed most rapidly at pH values above 7. Autolysis of whole cells of S. sanguis and one strain of S. mitis (ATCC15909) was maximal in 0-05 TO 0-2 M buffer, while the two S. mutans strains and S. mitis ATCC15912 showed maximal autolysis in 0-5 and 1-0 M buffers. Cultures harvested in the stationary phase of growth possessed only slightly decreased autolytic activity compared with those from the exponential phase. Whole cells autolysed more rapidly at 37 degrees C Than at 45 degrees C and 10 degrees C. Autolysis of isolated walls of three strains of S. mitis (ATCC903, ATCC15909 and ATCC15912) was maximal at pH 7-0 AND 7-5 and in 1-0 M buffers. Streptococcus mitis ATCC15909 also showed maximal lysis in 0-01 M and 0-5 M buffers. An endopeptidase action of the autolytic system of S. mitis ATCC15912 was indicated by the progressive release of soluble amino groups during autolysis of the walls. No release of reducing groups was observed. Several free amino acids were released during autolysis of these walls, alanine, lysine and glutamic acid being in greatest quanitity.
J Gen Microbiol 1976 Sep
PMID:Autolysis in strains of viridans streptococci. 1 Mar 49

E. coli K12 was found to utilise both D-and L-stereoisomers of alanine as sole sources of carbon, nitrogen and energy for growth. This capability was absolutely dependent upon the possession of an active membrane-bound D-alanine dehydrogenase, and was lost by mutants in which the enzyme was defective. The Michaelis constant for the enzyme with D-alanine as substrate was 30 mM, and the pH optimum about 8.9. D-alanine was the most active substrate, L-alanine was inactive and several other D-amino acids were 10--50% as active as D-alanine. Oxidation of D-alanine was linked to oxygen via a cytochrome-containing respiratory chain. Synthesis of the dehydrogenase was induced 16 to 23-fold by incubation with D- or L-alanine, but only D-alanine was intrinsically active as an inducer. L-alanine was active either as a substrate or inducer only in t he presence of an uninhibited alanine racemase which converted it to the D-isomer. The map-location of their structural genes between ara and leu, together with other similarities, indicate that D-alanine dehydrogenase and the "alaninase" of Wijsman (1972a) are the same enzyme. Both D- and L-alanine were intrinsically active as inducers of alanine racemase synthesis. The synthesis of both D-alanine dehydrogenase and alanine racemase was found to be regulated by catabolite repression.
Mol Gen Genet 1976 Dec 08
PMID:Biochemical, genetic, and regulatory studies of alanine catabolism in Escherichia coli K12. 1 92

Mutants of Pseudomonas aeruginosa PAO deficient in their utilization of DL-valine have been found to have lost their capacity to utilize DL-alanine and L-proline. Use of conjugal and transductional mediated gene transfers have established the chromosomal location of this gene and also its pleotropic function in the induction of the D-amino acid oxidase, involved in the oxidative utilization of DL-valine, DL-alanine and L-proline. These point mutations are clustered in a single locus designated as Val D and mapped around the 19th minute on the chromosome.
Mol Gen Genet 1978 Aug 04
PMID:Mapping of the locus involved in the catabolic oxidation of D-amino acids in Pseudomonas aeruginosa PAO. 3 39

The gustatory receptors of the eel palate were found to be extremely sensitive to amino acids and carboxylic acids. The results obtained are as follows: (a) 11 amino acids which are among naturally occurring amino acids elicited responses in the palatine nerve, but 9 amino acids did not elicit a response even at a high concentration. The effect of D-amino acids was always much less than that of their corresponding L-isomers. There was no appreciable difference in the effectiveness of an alpha-amino acid (alpha-alanine) and beta-amino acid (beta-alanine). (b) The threshold concentrations of the most potent amino acids (arginine, glycine) were between 10(-8) and 10(-9) M. A linear relation between the magnitude of the response and log stimulus concentration held for a wide concentration range for all the amino acids examined. (c) The palatine receptors responded sensitively to various carboxylic acid solutions whose pH was adjusted to neutral. The threshold concentrations varied between 10(-4) and 10(-7) M. The magnitude of the response at 10(-2) M increased with an increase of carbon chain length. (d) The extent of cross-adaptation was examined with various combinations of amino acids. A variety of the response patterns showing complete cross-adaptation, no cross-adaptation, or synergetic interaction was observed. The synergetic interaction was also observed when one amino acid below its threshold concentration was added to the other amino acid below its threshold concentration was added to the other amino acid. No cross-adaptation was observed between amino acids and fatty acids. (e) The treatment of the palate with papain led to loss of the responses to arginine, glycine, and histidine without affecting those to proline and acetic acid. The treatment with pronase E eliminated selectively the response to proline. The possibility that the eel gustatory receptors are responsible for sensing food at a distance was discussed.
J Gen Physiol 1979 Sep
PMID:Gustatory responses of eel palatine receptors to amino acids and carboxylic acids. 3 12

Compact-colony forming active substance (CCFAS), the material responsible for the compact colonies of Staphylococcus aureus observed in serum soft agar, was found to be an alkaline-stable, associated polysaccharide containing galactose, N-acetylglucosamine, ribitol, phosphorus and a small quantity of alanine. This substance, when extracted from strains unable to produce protein A clumping factor, was able to absorb the serum-reacting factor whereas a teichoic acid preparation of one strain could not. The formation of CCFAS was unaffected by the age of the cells, whereas when staphylococci were cultured at alkaline pH, young cells produced more clumping factor than old ones. Both fibrinogen and its degradation products were capable of inducing compact colonies in a strain of S. aureus. The ability of human sera to interact in compact-colony formation was independent of the immunoglobin content. Thus neither protein A, clumping factor, nor teichoic acid participate in the CCFAS reaction.
J Gen Microbiol 1977 Jan
PMID:Mechanism of compact-colony formation by strains of Staphylococcus aureus in serum soft agar. 6 87

Protein IX from adenovirus type 2 was purified by two methods, one from groups of nine hexons obtained by disrupting purified virus by heating in the presence of deoxycholate, and the other by a previously published method. The purified protein was used to obtain a monospecific antiserum. Protein IX was found to possess both sub-group- and type-specific antigenic determinants which were apparently accessible within the groups of nine hexons. Approximately 15 molecules of IX were found per group of nine hexons and from considerations of symmetry it seemed possible that IX was located at the 'corner to edge' contacts between hexons in the icosahedron. The protein in infected cells was found to possess approximately neutral charge as determined by immunoelectrophoresis. This was consistent with the amino acid composition, which showed it to be rich in serine, alanine and leucine with approximately half of its glutamic and aspartic acid residues amidified, and the isoelectric point of 6.0, as determined by two dimensional gel analysis. No free N-terminal amino acid was detectable. It is suggested that a unique tryptophan residue is located at around position 70 from the blocked N-terminus, on the basis of chemical cleavage by BNPS-skatole. Based on one tryptophan residue a total of 107 amino acids and a mol. wt. of 11200 was deduced. Analysis of 35S-methionine-labelled infected cell extracts in a two-dimensional gel system showed that the synthesis of polypeptide IX could be detected early in infection, i.e. in the presence of an inhibitor of DNA synthesis.
J Gen Virol 1979 Sep
PMID:Characterization of adenovirus protein IX. 9 18

A model has been proposed to account for growth inhibition by L-histidine in a variant strain of Nostoc muscorum. This strain has been characterized for its response to 3-amino-1,2,4-triazole and 1,2,4-triazole-3-alanine known to act as false core-pressors of the histidine biosynthesis genes. The histidine sensitive strain retained its sensitivity to triazole alanine while the inhibitory effects of aminotriazole were much reduced indicating a change in regulation of his genes. The probable interactions between nif and his genes in cyanobacteria (blue-green algae) have been discussed.
Mol Gen Genet 1979 Feb 16
PMID:Histidine sensitive variant of the blue-green alga Nostoc muscorum: response to corepressors of histidine biosynthesis. 10 14

The isolation and characterization of 29 new germination (Ger) mutants of Bacillus subtilis 168 is described. These were classified, along with previously described mutants, into seven groups according to map location. The mutations in 26 GerA mutants mapped between cysB and thr; detailed mapping of two of these has located them very close to citG. These mutants were deficient in germination in alanine, but responded to the germinative combination of asparagine, glucose, fructose and KCl. One GerB mutant mapped on the origin-proximal side of hisA; it was normal in germination in alanine, but deficient in termination in a mixture of asparagine, glucose, fructose and KCl. Two GerC mutants were linked to lys, but were separable from a temperature-sensitive growth deficiency mapping between lys and trp. The GerC mutants had a similar germination phenotype to the GerA mutants. Three GerD mutants did not germinate in either of the above germinants or in Penassay Broth. They were located on the side of ery distal to cysA. The GerE mutant, which did not germinate in any of the three germinants, was located very close to citF and possessed an altered spore coat. The two GerF mutants were defective in germination in all three germinants and mapped on the origin proximal-side of hisA, but much closer to his than did the GerB mutant. A phosphoglycerate kinase-negative mutant altered in germination mapped between cysB and hisA (GerG). These mutants have established a minimum of seven locations important to germination, and will be useful in the development and appraisal of theories of spore germination.
J Gen Microbiol 1979 Mar
PMID:Genetics analysis of spore germination mutants of Bacillus subtilis 168: the correlation of phenotype with map location. 11 Sep 6

An alkalophilic bacterium belonging to the genus Bacillus was isolated from an indigo ball. The bacterium exhibited a maximum growth rate at pH 10-0 TO 10-5. The incorporation of 14C-labelled amino acids or [14C]uracil, uptake of 14C-labelled alpha-amino isobutyric acid into the bacterium and oxygen consumption of the bacterium with amino acids as substrates were all maximum at pH 9-0 to 10-5. The uptake of [U-14C]glucose into the organism and oxygen consumption with carbohydrates, on the other hand, showed little variation of rate in the pH 8 to 10 region. The oxygen consumption of intact bacteria or protoplasts in culture medium was maximum at pH 10. The membrane of the bacterium oxidized NADH maximally at pH 7-5, and ATPase bound to the membrane exhibited maximum activity at pH 7.L-Lactate, L-alanine and malate dehydrogenases in the soluble fraction exhibited maximum activities at pH 7-4 to 8-4. The alkalophilic property of the bacterium may be due to the behaviour of the membrane towards charged substances admitted into the organisms.
J Gen Microbiol 1975 Feb
PMID:The basis of the alkalophilic property of a species of bacillus. 23 9

Among temperature resistant revertants of a temperature sensitive E. Coli alanyl-tRNA synthetase mutant a strain was found which contains an alanyl-tRNA synthetase with an additional mutation in the structural gene of the enzyme. This mutant enzyme has a 9 or 38 fold decreased Km value for alanine compared to that of the thermolabile parental enzyme or to wild-type enzyme, respectively. The alaS gene maps just counterclockwise from recA on the E. coli map (94% cotransduction frequency). It appears that the enzyme's increased affinity for alanine is the mechanism of suppressing the temperature sensitive character of the cell. In addition, some cold-sensitive temperature resistant revertants were found, where the cold-sensitive character mapped near strA. Presumably they are due to changes in ribosomal proteins as characterized by Ruffler et al. (1974).
Mol Gen Genet 1977 Nov 14
PMID:Suppression of a defective alanyl-tRNA synthetase in Escherichia coli: a compensatory mutation to high alanine affinity. 34 Sep 3


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