The cellular fatty acid compositions of 26 strains of methicillin‐resistant Staphylococcus aureus (MRSA) and 17 strains of methicillin‐susceptible S. aureus (MSSA) were analyzed by gas‐liquid chromatography. The fatty acid compositions of the two groups were very similar with 16 identified components. The major fatty acids were Ci14 = 0, Ci15 = 0, C18 = 0 and C20 = 0. Among these fatty acids, the percentage of the Ci15 = 0 fatty acid component of MRSA strains (11.4 ± 3.9%) was statistically higher than that of MSSA strains (6.2 ± 2.4%) (p < 0.001). On the other hand, the percentage of the C20 = 0 fatty acid components of MRSA strains (20.2 ± 8.8%) was statistically lower than that of MSSA strains (30.7 ± 10.4%) (p < 0.001). The production of beta‐lactamase and beta‐hemolysin in both groups' strain was also unrelated to the relative amounts of the fatty acid components. These results indicated a statistical tendency for the percentage fatty acid compositions of the MRSA strains to be quantitatively different from those of the MSSA for both the Ci15 = 0 and C20 = 0 fatty acid components. Analysis of the fatty acid compositions may have an application in the differentiation of MRSA and MSSA strains.

The culture fluids of various anaerobic bacteria induced the synthesis of early antigens (EA) in Epstein-Barr virus (EBV) carrying lymphoblastoid cells. The culture fluids of Corynebacterium butyricum and Fusobacterium nucleatum were the effective inducer on EA. The inducing activity was, to some extent, dependent on their n-butyric acid content, but appeared to be regulated by yet unidentified materials.

The purpose of this study was to examine the germicidal effect of the high oxidationpotential water (HOPW) on oral microorganisms, including pathogenic fungi, and the inhibitory effect of other

Abstract:It has been reported that methicillin-resistant strains of Staphylococcus aureus (MRSA) were slightly larger in coccal size than that of methicillin-susceptibe S. aureus (MSSA). However, the data in these reports were not exact because the observations by using microscope or transmission electron microscope on ultrathin sections were inadequate for measuring the coccal size.The coccal size was examined by using a scanning electron microscope. In addition, the width of cell walls was examined by using a transmission electron microscope on the ultrathin sections.Both mutant MSSA strains lost methicillin-resistance from MRSA strain and MRSA strains selected as heterogeneous strains from MSSA were used for measuring the morphological size compared with clinical strains of MRSA and MSSA.There were no significant differences in the coccal size and the width of the cell walls of MRSA, MSSA and mutant MRSA strains.However, the width of the cell walls of the MRSA strain selected from MSSA was about 85% larger than that of the parent MRSA strain. The effect might be influenced by the used antibiotics. These results revealed that the differences between MRSA and MSSA strains were not significantly

The STAPHYOGRAM kit system was compared with Kloos' simplified method for identifying coagulase-positive staphylococci isolated from human oral cavities. In addition, we determined whether or not the code numbers in the kit, which purportedly represent biochemical characteristics, correlated with the biological tests.Gram-positive cocci isolated from oral cavities were first examined for catalase and coagulase activities, DNase production and mannitol fermentation species of the isolates that were positive for these four tests was subsequently confirmed using the STAPHYOGRAM kit.Of the 34 isolates that were assumed to be strains of Staphylococcus aureus by the first four tests, 31 (91%) were assigned 13 code numbers and identified as S. aureus by the STAPHYOGRAM kit. Code numbers 723346 and 723347 were each represented by 14 strains (45% of the total). The remaining 11 code numbers accounted for less than 9% of the strains. The 13 code numbers were not related to the production of pigment or hemolysin.However, code numbers 723346 and 723347 were thought to be related to the coagulase type VII since 67 to 80% of the strains with these numbers showed this coagulase type.These results indicate that the STAPHYOGRAM kit system is useful in the identification and biochemical characterization of S. aureus in oral cavities.