Presence of Cell Wall Lytic Enzyme in Stable Staphylococcal L-Form

The stable L-form cells derived from Staphylococcus aureus 209P were examined for the presence of cell wall lytic enzymes. The enzyme preparations from cells and culture fluid of the parent strain lysed both Micrococcus lysodeikticus cells and S. aureus cells, whereas the enzyme preparations from the L-form lysed M. lysodeikticus cells but not S. aureus cells. Lipoteichoic acid, which has been reported to be a regulator of the lytic enzyme, inhibited both enzyme preparations from the parent strain and the L-form. However, the susceptibility of the enzyme preparation from the L-form to lipoteichoic acid was lower than that from the parent strain

Penicillin Resistance of Pseudomonas aeruginosa Clinical Isolates from Urinary Tract Infections

One hundred and thirteen clinical isolates of Pseudomonas aeruginosa from urinary tract infections were tested for their mechanisms of resistance to penicillins. Ninety-eight percent and 100.0% of the strains were resistant (MIC≧100 μg/ml) to ampicillin and penicillin G, respectively, while only 5.3% were resistant to piperacillin. Low permeability of the outer membrane, and penicillinase production were involved in their resistance mechanisms. Peptidoglycan synthesis in ether-treated cells of two representative strains was inhibited by ampicillin and piperacillin at the concentrations markedly lower than that for penicillin G

Frequency and Distribution of Candida Species from Denture Wearers

Species of Candida were isolated from 100 denture wearers, who were examined for grade of denture stomatitis, degree of denture plaque accumulation and other clinical features. Candida albicans was the dominant species isolated from denture surfaces followed by Torulopsis glabrata and Candida tropicalis. Statistical analysis of the results revealed close relationships between the grade of denture stomatitis and the degree of denture plaque accumulation or the fungal concentration on the denture surface, and also between the degree of denture plaque accumulation and fungal concentration on the denture surface. Furthermore, the grade of denture stomatitis correlated with the period of denture wearing but not with the patient's age. The fungal concentration on denture surface also correlated with the patient's age and the period of denture wearing

Effect of Saliva on Candidal Adherence to Polymethyl Methacrylate Resin

The adherence of Candida species to saliva-coated plates of polymethyl methacrylate resin was studied physico-chemically. Saliva-coating of the resin plate caused increasing adherence of C. albicans, whereas it caused decreasing adherence of C. tropicalis. The hydrophobicities of the surfaces of the resin plate and the candidal cells were evaluated by a contact angle method, and surface free energies of these surfaces were calculated. The candidal cell adherence to the saliva-coated plates was highly correlated with the free energy change in hydrophobic interaction