The production of extracellular deoxyribonuclease was examined with anaerobic organisms isolated from clinical specimens. Nuclease activity was extraordinarily common. All strains of Fusobacterium, including eight species, as well as Bacteroides fragilis and B. melaninogenicus, displayed enzyme activity. Whereas the gram-positive bacteria were generally less productive, all strains of Clostridium perfringens, Peptostreptococcus intermedius, and P. anaerobius specifically produced deoxyribonuclease. The test is taxonomically valuable, particularly in the characterization of gram-positive cocci, since a deoxyribonucleaseproducing coccus indicates P. intermedius or P. anaerobius. Additionally, possession of the enzyme may prove to be a useful correlate of the potential pathogenicity of anaerobes.

Anaerobic organisms were tested for phosphatase activity in different pH ranges. Several groups of organisms displayed characteristic patterns. Bacteroides fragilis, B. melaninogenicus, and B. ruminicola produced phosphatase with strongest activity at pH 8.6. Fusobacterium mortiferum was the only species of this genus to show strong hydrolysis. The enzyme was active in both acid and alkaline ranges. The activity of gram-positive organisms was variable, the most active groups being Clostridium perfringens, Peptostreptococcus intermedius, P.

Susceptibility testing of 96 clinical group IVe isolates to 19 antimicrobial agents by agar dilution revealed that, at drug levels achievable in serum, the isolates were susceptible only to aminoglycosides, cephalosporins, and colistin, whereas at drug concentrations attainable in urine, they were susceptible to erythromycin, tetracycline, and nitrofurantoin as well.In a 2-year study at

A total of 153 clinical isolates and 10 reference strains were employed in an investigation of C02-dependent streptococci. Their selection was based on a lactic acid homofermentative end product. This group of organisms grew best in 5 to 10% C02, and several species, including Streptococcus mutans, S. intermedius, Streptococcus MG, S. anginosus, and S. constellatus, required increased C02 for primary recovery. A basal medium of thioglycolate with 0.1% Tween 80 and phenol red was prepared and used with selected carbohydrates. This media provided luxuriant growth. Serological testing failed to give any definitive correlation with species identification. A shortened differentiation scheme, combined from previous studies, was proposed.

A sensitive, specific, and rapid enzyme-linked immunosorbent assay has been developed for the detection of immunoglobulin G to Staphylococcus aureus teichoic acid in human sera. Detection of S. aureus teichoic acid antibody is at least 800 times more sensitive than a double diffusion in gel assay, and positive titers of 1:25,600 and greater were observed with this assay. Results with the enzyme-linked immunosorbent assay can be obtained within 3.5 h by using antigen-coated cuvettes. Quantitation of S. aureus teichoic acid antibody by this enzyme-linked immunosorbent assay may be useful in the initial as well as the follow-up diagnosis of serious S. aulreus infections.