Attempts were made to purify and study the kinetics of extracellular phospholipase A of Salmonella newport (6,8, eb; 1,2). The enzyme was purified by salt precipitation followed by gel filtration, using different grades of Sephadex. The enzymically active purified preparation was found to be a protein, having molar mass ranging between 43 and 67 kDa. The enzyme had a pH optimum at 7.5, giving 18.2 micrograms of lysophosphatidylcholine per mg protein. Its activity was enhanced by all metal ions except potassium, by solvents and surfactants except sodium dodecyl sulfate. It hydrolyzed the membrane phospholipids of red blood cells and was inhibitory to the growth of other microorganisms.

• MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• fosfolipasy A izolace a purifikace   metabolismus   MeSH
• gelová chromatografie MeSH
• kinetika MeSH
• Salmonella enzymologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfolipasy A MeSH

Fifteen uroisolates of E. coli were studied for both cell-free and cell-bound hemolysin production. Estimations were done in Trypticase soy broth (TSB, providing iron-replete medium) TSB + 2,2'-bipyridine (providing experimentally created iron-depleted conditions) and pooled normal human urine (providing natural iron-depleted growth medium). In TSB 40% of strains showed no detectable cell-free hemolysin, they were able to produce it in the presence of 2,2'-bipyridine and more so when grown in urine. The cell-bound hemolysin was produced by all the strains in TSB, but in the presence of 2,2'-bipyridine and urine an insignificant increase was observed. All the strains when given 2nd and 3rd passage in urine, were found to elaborate significantly more cell-free as well as cell-bound hemolysin.

• MeSH
• bakteriální proteiny biosyntéza   MeSH
• Escherichia coli růst a vývoj   izolace a purifikace   metabolismus   MeSH
• hemolyziny biosyntéza   MeSH
• kultivační média MeSH
• lidé MeSH
• moč * MeSH
• proteiny z Escherichia coli * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• hemolyziny MeSH
• Hlya protein, E coli MeSH Prohlížeč
• kultivační média MeSH
• proteiny z Escherichia coli * MeSH

The virulence of a silver-ion-resistant (AgR) clinical isolate of Pseudomonas aeruginosa and its silver-sensitive mutant (AgS) was compared in the murine burn-wound sepsis model. The AgR strain showed significantly higher colonization of burned skin vis-a-vis the AgS strain. The altered pathogenicity may in part be due to the decrease in capsular content and cell surface hydrophobicity, accompanying the loss of silver ion resistance. The AgR and AgS strains, however, did not exhibit quantitatively significant differences in the production of extracellular hemolysins and proteinases.

• MeSH
• antibiotická rezistence genetika   MeSH
• infekce v ráně etiologie   MeSH
• modely nemocí na zvířatech MeSH
• mutace MeSH
• myši MeSH
• popálení komplikace   MeSH
• pseudomonádové infekce etiologie   MeSH
• Pseudomonas aeruginosa účinky léků   genetika   patogenita   MeSH
• stříbro farmakologie   MeSH
• virulence genetika   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• stříbro MeSH

As phospholipases of mycoplasma species may play a role in the pathogenesis of respiratory tract and urogenital tract diseases Mycoplasma mycoides and Acholeplasma laidlawii were examined as to the production of phospholipase A2 (PLA) and attempts were made to purify and characterize it. Both species produced PLA. The purified enzyme was found to be heat-labile, active at alkaline pH, revealing a single band in polyacrylamide gel electrophoresis. Metal ions such as calcium and barium, increased its activity whereas solvents at high concentrations decreased it. It was resistant to surfactants.

• MeSH
• Acholeplasma laidlawii enzymologie   MeSH
• extracelulární prostor enzymologie   MeSH
• fosfolipasy A izolace a purifikace   metabolismus   MeSH
• fosfolipasy A2 MeSH
• fosfolipasy metabolismus   MeSH
• gelová chromatografie MeSH
• koncentrace vodíkových iontů MeSH
• Mycoplasma mycoides enzymologie   MeSH
• vápník farmakologie   MeSH
• vysoká teplota MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfolipasy A MeSH
• fosfolipasy A2 MeSH
• fosfolipasy MeSH
• vápník MeSH