A microorganism utilizing quinolinic acid as sole carbon, nitrogen, and energy sources for growth, and producing a potent activity of quinolinate phosphoribosyltransferase in its cells was isolated. Based on its morphological, cultural, physiological, and biochemical characteristics, including the proper composition of cellular fatty acids, Alcaligenes eutrophus subsp. quinolinicus subsp. nov. KOUNO and IWAI is proposed for this organism.
Two new yeasts, Candida mamillae from spilt milk on isoprene nipple of a nursing bottle and Candida placentae from commercial sweet and creamy cake, are described on the basis of taxonomic characteristics commonly employed.
In sonic extracts, the electron transport system of a psychrotrophic Pseudomonas sp. strain 351 (P. 351) was operating more actively than that of P. aeruginosa at 25° and below. The coupled phosphorylation in P. 351 was also brought about by as much as about three times that in P. aeruginosa at 7°. The activities of the NADH oxidation and the coupled phosphorylation were influenced by the growth temperatures in P. 351, but not in P. aeruginosa. The P/O ratios in the sonic extracts of P. 351, P. aeruginosa, and Vibrio sp. strain ABE-1, a psychrophile, were higher at 7° than at 25°, even when the growth temperatures were varied. The efficiency of the coupled phosphorylation does not seem to be depressed under lower temperatures in these bacteria.
Localization of enzymes in Fusarium oxysporum was investigated. It was found that invertase and sulfhydryl oxidizing activity were localized in the isolated cell-wall fraction of mycelia and microconidia of this fungus, prepared either by toluene and pronase treatment or mechanical disruption. The distribution of the enzyme activities was quite different from that of intracellular localizing enzymes. The physiological implication of the localization of these enzymes was discussed.
Four small DNA-containing bacillus phages, M2, Nf, φ29, and φ15, could be classified into two groups according to their response to anti-phage sera and other experimental results; M2 and Nf belong to one group, and φ29 and φ15 to another group. The presence of 6-(p-hydroxyphenylazo) uracil has no effect on the production of these phages, but nalidixic acid inhibits their growth significantly as reported for φ29.
The requirement of wild-type Neurospora crassa for biotin in growth and survival was examined. Extensional growth rates during biotin depletion were measured. With egg-white avidin to sequester trace biotin contamination in purified medium, the requirement was absolute. The presence of the free radical scavenger, nordihydroguaiaretic acid (NDGA), enhanced growth rate during either moderate or severe biotin limitation. Conidia did not undergo biotinless death, even in the presence of avidin. Apparently, endogenous biotin concentration was sufficient for survival. Since biotin is a cofactor for fatty acid synthesis and biotin deficiency depletes the cellular lipid content, the results of these experiments are consistent with the hypothesis that nutritional deficiencies in lipid and membrane synthesis leading to synthesis of abnormal membranes promote excessive lipid peroxidation and free radical damage and, consequently, cellular senescence. Inhibition of these processes by NDGA therefore enhances the cellular growth rate with limiting biotin.
Electrophoretic patterns of esterase, acid phosphatase, tyrosinase, malate dehydrogenase (MDH, NAD, and NADP dependent), glucose-6-phosphate dehydrogenase (G-6-PDH), and 6-phosphogluconate dehydrogenase (6-P-GDH) were investigated in extracts of mycelium, primordium, stipe, pileus, and hymenophore of carpophore in Lentinusedodes AJ 8541, and esterase patterns were determined in extracts of Coprinus kirnurae AJ 8239 and Polyporellus brumalis AJ 8169. Esterase, tyrosinase, MDH (NAD dependent), and 6-P-GDH appeared in the isozyme, and only esterase showed different patterns in mycelium, primordium, stipe, and pileus. No difference was found in electrophoretic patterns of other enzymes.