Effect of calcium on Pseudomonas aeruginasa and Bacillus cereus metabolites / Efeito do cálcio nos metabólitos de Pseudomonas aeruginasa e Bacillus cereus

The effects of Calcium (Ca+²) on virulence and some parameters should be analyzed in this study. Pseudomonas aeruginosa Gram (-) and Bacillus cereus Gram (+) were used. Both bacteria are soil bacteria. In this study; the effect of Ca+² on protease, amylase, LasB elastolytic assay, H2O2, pyorubin and biofilm on metabolites of these bacteria were investigated during 24 hour time. In this study, the effect of Ca+² on the production of some secondary metabolites on P. aeruginosa and B. cereus was investigated and presented for the first time by us.

Os efeitos do cálcio (Ca+²) na virulência e alguns parâmetros devem ser analisados neste estudo. Pseudomonas aeruginosa Gram (-) e Bacillus cereus Gram (+) foram usados. Ambas as bactérias são bactérias do solo. Neste estudo, o efeito do Ca+² sobre a protease, amilase, ensaio elastolítico LasB, H2O2, piorubina e biofilme nos metabólitos dessas bactérias foram investigados durante 24 horas. Neste estudo, o efeito do Ca+² na produção de alguns metabólitos secundários em P. aeruginosa e B. cereus foi investigado e apresentado pela primeira vez por nós.

[Prevalence of nano structure S-layer and beta-lactamase in Bacillus cereus strains]

S-layer is the outer protein layer in the most archaea and bacteria. S-layer protects bacteria against phagocytosis and prohibits entry of some biomolecules and some antibiotics and adhesion to matrix proteins. S-layer is a virulence agent in bacteria, beta-lactamase can inactive [beta-lactame antibiotics. According to role of beta-lactame antibiotics in the treatment of infectious diseases with Bacillus spp., increasing frequency of S-layer and beta-lactamase producer Bacillus cereus strains in hospitals lead to increase antibiotic resistant nosocomial infections. In this basic study, 274 samples were evaluated with laboratory methods in Alzahra hospital and Isfahan University between 2004 and 2006. Bacterial identification was performed with microbiological methods, such as staining, chemical test, use of differential and selective Bacillus cereus selective agar media. Bacteria cultured in TSA for 16h, and then separated surface proteins, and finally electrophoresis was performed. S-layer in Bacillus cereus has 97KD molecular weight. Production of beta-lactamase was evaluated by acidometric method. Of 247 isolated bacteria, frequency of Bacillus cereus strains, S-layer and beta-lactamase in S-layer producer Bacillus cereus strains were 9.49%, 46.20% and 100%, respectively. Results showed high prevalence of nano structure S-layer and beta-lactamase producer Bacillus cereus strains in hospital. We recommend controlling bacterial population in crowded places and health and therapeutic centers to decrease producing antibiotic resistance bacteria

Evaluation of product analogues for purification of penicillinase by affinity chromatography.

Among different matrices prepared, ampicilloic acid-polymer matrix offered 86.7% adsorption, 95% elution and 82.4% overall recovery of penicillinase. The structure of both the side chain and penicilloic or cephalosporoic acid moieties contribute to the affinity interactions.

Activity and stability of Bacillus cereus penicillinase entrapped in aerosol OT reverse micelles.

The kinetics of enzyme catalyzed hydrolysis of penicillin G and stability of the enzyme alpha-penicillinase, entrapped in aerosol OT reverse micellar droplets have been investigated spectrophotometrically. Various physical parameters, such as, water pool size (related to Wo), pH and temperature, were optimized for maximum activity of penicillinase in water/aerosol OT/isooctane reverse micelles. The enzyme showed maximum activity of Wo - 14 and pH, 7.0. At any temperature the enzyme was to be more active in reverse micelles than in aqueous solution. At optimum conditions of Wo, pH and temperature the enzyme was 100% more active in reverse micelles than its maximum activity in aqueous solution. In both the systems, the activity starts falling at and above 25 degrees C. CD Spectral studies showed that the enzyme in reverse micelles possesses more helical structure than it has in aqueous solution and at the optimum conditions in which it showed maximum activity, the alpha-helicity was also maximum. The enzyme was very stable in reverse micelles at and above room temperature compared to the same in aqueous solution.