The enzymic hydroxylation of progesterone at C-11, C-17, and C-6 with a local strain of Trichothecium roseum was investigated when the fermentation medium was supplemented with different compounds including organic acids, amino acids, vitamins, as well as some inorganic salts. The rate of conversion of progesterone and its enzymic hydroxylation at a specific position were affected in a different manner. The addition of oxalate as well as valine and phenylalanine to the medium stimulated the substitution of progesterone at C-11 and C-17 positions. Similar results were recorded with riboflavin and nicotinic acid. The 11α-hydroxylation reaction was specifically induced with acetate and fumarate. Maximal yields of 17α-hydroxyprogesterone were obtained on the addition of ZnSO4•7H2O (0.3g/liter), FeSO4•7H2O (0.2g/liter) or CaCl2 (0.3g/liter) to the fermentation medium. In most cases, the yield of 11α-hydroxyprogesterone was slightly affected with these salts. However, the iron salt at a concentration 0.1g/liter supported the formation of 11α-hydroxyprogesterone in a relatively high yield. The formation of dihydroxy derivatives, 11α, 17α- and 6β, 11α-dihydroxyprogesterone, under different experimental conditions is discussed.
Two strains of catabolite repression-insensitive mutant, TAB40-303 and TAB40-203, were isolated. TAB40-303 was a mutant not specific for tryptophanase synthesis and seemed to be injured at a point in glucose catabolism. Tryptophanase formation by TAB40-203 was not influenced by any carbon sources and not affected by adenosine 3′, 5′-cyclic monophosphate (c-AMP) which were effective in the parent strain. The mutant was presumed to be injured at the site at which c-AMP acted. Phosphoenolpyruvate (PEP) was again shown to be closely related to the catabolite repression by using these mutants.
Among 100 cultures of lactic acid bacteria screened for caseinolytic activity, 13 streptococci and 15 lactobacilli showed clearance zones of proteolysis. Out of 12 cultures examined for caseinolysis after 14 days of growth in chalk milk, maximum activity was noted in L. bulgaricus 15 and S. faecalis 52. Substantial increase in caseinolysis occurred during early stages of incubation in media containing 2.5% casein. L. bulgaricus 15 and S. faecalis 52 degrade K-casein fraction more readily thanαs- or β-fraction.
Clostridium saccharoperbutylacetonicum was induced to lyse by exposure to mitomycin C, with a concomitant production of bacteriocin (clostocin O). The mature lysis began about 180min after mitomycin C treatment and completed after 5hr or more. By the treatment with various antibiotics, premature lysis was provoked before 180min, as follows: 1) Chloramphenicol, oxytetracycline and many other antibiotics inhibited the induction of lysis, when added during the first 90min, by preventing the synthesis of clostocin O-endolysin. However, when they were added at a later period, at which the active endolysin was apparently synthesized in the organisms, they provoked premature lysis of the organisms. The premature lysis began 5 to 30min after the addition of antibiotics, and finished after about 60min, when the correct concentration of antibiotics was used. The lag period after addition of antibiotics before lysis began differed from one antibiotic to another. The rate of lysis was accelerated according to the increased content of endolysin and to the increased concentration of antibiotics. Among the many antibiotics used, protein synthesis inhibitors were the most effective in inducing premature lysis. In the case of oxytetracycline-resistant mutant, the premature lysis was not provoked by oxytetracycline, but was by chloramphenicol, etc. From these results it was considered that premature lysis of mitomycin C-treated organisms was due both to the action of clostocin O-endolysin and to some metabolic perturbation of protein synthesis resulting from antibiotic treatment. 2) Penicillin, cephaloridine, and cephalosporin C did not inhibit the synthesis of endolysin. Their action on the premature lysis was very different from those of many other antibiotics described above. Mitomycin C-treated organisms were provoked by them to lyse prematurely even when added early in the induction process. However, the actual lysis did not begin until the active endolysin appeared in the organisms, because the content of active endolysin originating from the normal organisms became very small after mitomycin C treatment. It was concluded that the inhibition of cell wall synthesis or its related protein synthesis resulted in premature lysis in the presence of clostocin O-endolysin. It was further discussed that the mature lysis might be determined by the decline in wall synthesis in addition to the action of endolysin.
Lysis of Clostridium saccharoperbutylacetonicum was induced by mitomycin C treatment, with a concomitant production of bacteriocin (clostocin O) and its endolysin. The cellular lysis produced by the endolysin was drastically stopped by the addition of fradiomycin (neomycin) at above 100μg/ml. In an in vitro reaction system, fradiomycin also inhibited the action of isolated endolysin upon the Formalin-treated organisms and cell wall used as the substrate of Cl. Saccharoperbutylacetonicum. Therefore, fradiomycin seemed to be a specific inhibitor against the activity of clostocin O-endolysin. Similar effects were observed with kanamycin, novobiocin, streptomycin, viomycin, and polymyxcin B.
Edited and published by : Applied Microbiology, Molecular and Cellular Biosciences Research Foundation/Center for Academic Publications Japan Produced and listed by : TERRAPUB, Center for Academic Publications Japan/Shobi Printing Co., Ltd. (-Vol.60,No12), Center for Academic Publications Japan/InternationalAcademic Printing Co., Ltd.(-Vol.54,No1)