-
Voprosy Pitaniia 1985
Review
Topics: Animals; Bacteriological Techniques; Environmental Microbiology; Feces; Food; Food Handling; Food Microbiology; Food Preservation; Humans; Meat Products; Proteus; Proteus mirabilis; Proteus vulgaris; Sewage
PubMed: 3885570
DOI: No ID Found -
The Journal of Antibiotics Jul 1986A cephalosporin-hydrolyzing enzyme from strains of Proteus penneri resistant to beta-lactam antibiotics was purified and characterized. The enzyme gave a single protein...
A cephalosporin-hydrolyzing enzyme from strains of Proteus penneri resistant to beta-lactam antibiotics was purified and characterized. The enzyme gave a single protein band on SDS-polyacrylamide gel electrophoresis with a molecular weight of 30,000. This cephalosporinase has an isoelectric point of 6.8, a pH optimum of 6.5 and a temperature optimum of 45 degrees C. The enzyme hydrolyzed cephaloridine, cephalothin, cefuroxime, and cefotaxime more rapidly than penicillins. The relative rate, with cephaloridine as 100, were: cephalothin, 50; cefuroxime, 93; cefotaxime, 48; ceftriaxone, 23; cefoperazone, 11; benzylpenicillin, 3; ampicillin, 9; and carbenicillin, less than 1. Cephamycins had low affinities for the enzyme. However, clavulanic acid and sulbactam, with high affinities for the enzyme, were inhibitors of this enzyme.
Topics: Anti-Bacterial Agents; Molecular Weight; Proteus; beta-Lactamases; beta-Lactams
PubMed: 3489701
DOI: 10.7164/antibiotics.39.938 -
Journal of Bacteriology Oct 1970The lipids from three types of organisms-a Proteus mirabilis wild type highly resistant to polymyxin B, a polymyxin B-sensitive mutant derived from the wild type, and...
The lipids from three types of organisms-a Proteus mirabilis wild type highly resistant to polymyxin B, a polymyxin B-sensitive mutant derived from the wild type, and the wild type grown in the presence of sulfadiazine resulting in phenotypic conversion to polymyxin B sensitivity-were examined to determine the nature of polymyxin B resistance. The phospholipid compositions were nearly identical; each organism contained similar small amounts of N-methyl phosphatidylethanolamine in addition to comparable quantities of phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. the fatty acid compositions were similar in the exponential phase of growth; in the stationary phase, sulfadiazine markedly inhibited the synthesis of cyclopropane fatty acids. Liposomes prepared from the dried lipids of the three types of organisms were extensively and similarly disrupted by the polymyxin. These findings suggest that polymyxin B resistance in P. mirabilis is determined by the cell envelope which prevents access of the antibiotic to the susceptible lipid target sites.
Topics: Chromatography; Drug Resistance, Microbial; Drug Synergism; Fatty Acids; Phospholipids; Phosphorus Isotopes; Polymyxins; Proteus; Sulfadiazine
PubMed: 4319722
DOI: 10.1128/jb.104.1.289-294.1970 -
Journal of Medical Microbiology May 1979The motilities of Proteus long forms during swarming on agar were measured on cells transferred to liquid suspension. During concentric-ring formation on solid medium,...
The motilities of Proteus long forms during swarming on agar were measured on cells transferred to liquid suspension. During concentric-ring formation on solid medium, when the edge of the swarm was advancing slowly or had stopped, the velocity of long-form motility was low. When the colony was spreading rapidly, long-form velocitywas relatively high. This periodic variation in cell velocity, which determines the zones formed during swarming, cannot adequately be explained by negative chemotaxis.
Topics: Bacteriological Techniques; Chemotaxis; Movement; Proteus mirabilis; Proteus vulgaris
PubMed: 379339
DOI: 10.1099/00222615-12-2-195 -
The Journal of Heredity Mar 2019We provide a comparative population genetic study of the elusive amphibian, Proteus anguinus, by comparing the genetic diversity and divergence among 4 cave populations...
We provide a comparative population genetic study of the elusive amphibian, Proteus anguinus, by comparing the genetic diversity and divergence among 4 cave populations (96 individuals) sampled in the Dinaric Karst of Croatia. We developed 10 variable microsatellite markers using pyrosequencing and applied them to the 4 selected populations belonging to 4 different cave systems. The results showed strong genetic differentiation between the 4 caves corroborating with previous findings suggesting that Proteus might comprise several unrecognized taxa. Our results confirmed that gene flow should be high within the caves, whereas it is low between hydrographic systems since geological periods. Finally, we conclude that the high genetic subdivision suggests the necessity of treating the 4 studied Proteus populations as evolutionary significant units.
Topics: Biological Evolution; Croatia; Genetic Variation; Genetics, Population; Geography; Microsatellite Repeats; Population Density; Proteus; Repetitive Sequences, Nucleic Acid
PubMed: 30576453
DOI: 10.1093/jhered/esy067 -
Journal of Bacteriology Apr 1967Urease of Proteus rettgeri is an inducible enzyme synthesized specifically in the presence of urea; urea analogues did not act as inducers. Once initiated, the...
Urease of Proteus rettgeri is an inducible enzyme synthesized specifically in the presence of urea; urea analogues did not act as inducers. Once initiated, the biosynthesis of the enzyme proceeded as a constant fraction of the total protein formed. The rate of urease formation was affected by the carbon source used. In comparison with glycerol, glucose inhibited enzyme synthesis. The addition of ammonium ions to the inducing medium also decreased the rate of urease biosynthesis, and when ammonium ions were present urease activity and urea transport across the cell membrane were inhibited. A kinetic analysis of urease inhibition by ammonium ions, by use of a partially purified preparation of urease, showed that it was a competitive inhibition.
Topics: Cell Membrane Permeability; Enzyme Induction; Enzymes; Glucose; Kinetics; Proteus; Quaternary Ammonium Compounds; Thiourea; Urease
PubMed: 6032508
DOI: 10.1128/jb.93.4.1294-1301.1967 -
Biotechnology Advances Nov 2017Enantiomerically pure amino acids are of increasing interest for the fine chemical, agrochemicals and pharmaceutical industries. During past years l-amino acids have... (Review)
Review
Enantiomerically pure amino acids are of increasing interest for the fine chemical, agrochemicals and pharmaceutical industries. During past years l-amino acids have been produced from deracemization of dl-solution employing the stereoselective flavoenzyme d-amino acid oxidase. On the other hand, the isolation of corresponding d-isomer was hampered by the scarce availability of a suitable l-amino acid oxidase activity. On this side, l-amino acid deaminase (LAAD), only present in the Proteus bacteria, represents a suitable alternative. This FAD-containing enzyme catalyzes the deamination of l-amino acids to the corresponding α-keto acids and ammonia, with no hydrogen peroxide production (a potentially dangerous oxidizing species) since the electrons of the reduced cofactor are transferred to a membrane-bound cytochrome. Very recently the structure of LAAD has been solved: in addition to a FAD-binding domain and to a substrate-binding domain, it also possesses an N-terminal putative transmembrane α-helix (residues 8-27, not present in the crystallized protein variant) and a small α+β subdomain (50-67 amino acids long, named "insertion module") strictly interconnected to the substrate binding domain. Structural comparison showed that LAAD resembles the structure of several soluble amino acid oxidases, such as l-proline dehydrogenase, glycine oxidase or sarcosine oxidase, while only a limited structural similarity with d- or l-amino acid oxidase is apparent. In this review, we present an overview of the structural and biochemical properties of known LAADs and describe the advances that have been made in their biotechnological application also taking advantage from improved variants generated by protein engineering studies.
Topics: Amino Acids; Aminohydrolases; Biotechnology; D-Amino-Acid Oxidase; Enzymes; Protein Engineering; Proteus
PubMed: 28782586
DOI: 10.1016/j.biotechadv.2017.07.011 -
Journal of Medical Microbiology Feb 1973
Topics: Microscopy, Phase-Contrast; Movement; Proteus
PubMed: 4570478
DOI: 10.1099/00222615-6-1-33 -
Applied Microbiology Jun 1968The number of strains of Proteus studied was 413, and these were obtained from all clinical materials with the exception of fecal specimens. Lactose was fermented by 37...
The number of strains of Proteus studied was 413, and these were obtained from all clinical materials with the exception of fecal specimens. Lactose was fermented by 37 strains (P. inconstans, 29%; P. rettgeri, 16%; P. mirabilis, 4.2%; P. morganii, 3.6%; and P. vulgaris, 0%) of which 33 were from the genitourinary system. These 33 strains constituted 12.7% of the 260 strains isolated from this source. Biochemically, P. mirabilis was the least variable, and P. rettgeri was the most variable of the five species of Proteus tested. P. inconstans and P. rettgeri resembled each other more closely than any of the other species of Proteus. Comparison of results obtained in the Memphis area with those found in other locations showed that biochemical characteristics varied most with the substances citrate, salicin, xylose, trehalose, and mannitol. In contrast to earlier reports from Israel and England, none of the strains of P. inconstans in the present study was able to attack urea. All five species of Proteus tested (by the disc method) were highly susceptible to methenamine mandelate. P. mirabilis, P. morganii, and P. vulgaris were also highly susceptible to nitrofurantoin. All strains of P. mirabilis were susceptible to ampicillin. P. inconstans was the most resistant species of Proteus. Of the other 356 urease-positive strains tested, 79% were susceptible to chloramphenicol, whereas only 3.8% of the 56 urease-negative strains (P. inconstans) were susceptible. When tested with streptomycin, 61% of urease-positive strains were susceptible and 1.8% of the urease-negative strains were susceptible. Of 36 lactose-positive strains, 33.8% were susceptible to chloramphenicol, whereas 72.8% of all lactose-negative strains were susceptible. Again, of the lactose-positive strains, 17% were susceptible to streptomycin, whereas 56.3% of all lactose-negative strains were susceptible.
Topics: Anti-Bacterial Agents; Anti-Infective Agents, Urinary; Drug Resistance, Microbial; Geography; Humans; Lactose; Proteus; Respiratory System; Tennessee; Urogenital System; Wound Infection
PubMed: 5664111
DOI: 10.1128/am.16.6.881-889.1968 -
Zhurnal Mikrobiologii, Epidemiologii I... Dec 1974
Review
Topics: Animals; Bacteria; Biochemical Phenomena; Biochemistry; Ecology; Humans; Industrial Waste; Intestines; Proteus; Proteus mirabilis; Proteus vulgaris; Sewage; Water Microbiology
PubMed: 4616553
DOI: No ID Found