Methods are described that resulted in the selective release of deoxyribonucleic acid (DNA)-binding factor from the surface of competent pneumococci. The same methods caused a parallel inactivation of the DNA-binding capacity of the extracted bacteria. Genetically or physiologically incompetent pneumococci did not yield binding factor upon exposure to the same methods. The solubilized binding f...

PNEUMOCOCCI, LIVING OR DEAD, ARE SOLUBLE IN BILE WHEN: (a) the autolytic enzymes are still present in a potentially active form; (b) conditions are favorable for enzymatic action. Bile solubility of pneumococci involves as a necessary step one, or a few, of the many stages of the autolytic complex. These observations hold true for the disruption of pneumococci by freezing and thawing, by previo...

The pneumococcal virulence factors include capsule, PspA, PspC, and Ply. Cytometric analysis demonstrated that the greatest levels of C3 deposition were on a Deltaply PspA(-) PspC(-) mutant. Also, Ply, PspA, and PspC expression resulted in C3 degradation in vitro and in vivo. Finally, blood clearance assays demonstrated that there was enhanced clearance of Deltaply PspA(-) PspC(-) pneumococci c...

The distribution of subclasses mefA and mefE of the mefA gene among 116 M-phenotype streptococci was as follows: pneumococci (38 strains had mefE and 4 mefA), viridans streptococci (49 mefE and 1 mefA), and Streptococcus pyogenes (24 mefA). Spain(9V)-3-14 and England(14)-9 clones of serotype 14 were dominant among pneumococci.

To directly examine the role of hydrogen peroxide in the killing of bacteria after ingestion by granulocytes, we have studied some of the events of phagocytosis of a mutant strain of pneumococci which is relatively deficient in peroxide production. The hydrogen peroxide-deficient pneumococci and the otherwise identical wild type were grown with [(14)C]arachidonic and [(3)H]palmitic acid labels ...

To determine prevalence and genetic structures of new serotype 6D strains of pneumococci, we examined isolates from diverse clinical specimens in South Korea during 1991-2008. Fourteen serotype 6D strains accounted for 10.4% of serogroup 6 pneumococci from blood, sputum, nasopharynx, and throat samples. Serotype 6D strains consisted of 3 sequence types.

bacterial resistance to antibiotics is a serious problem and is increasing in prevalence world-wide at an alarming rate. the antimicrobial susceptibility patterns of 1897 gram-positive bacterial isolates were evaluated. the minimum inhibitory concentration (mic) of isolates which comprised staphylococcus aureus (927 isolates), coagulase-negative staphylococci (cns; 425 isolates), enterococcus f...