A further characterization of Actinomyces tumemacerans KRASSILNIKOV and KOVESHNIKOV, 1962 strain INMI P-42 was carried out. It is classified in Section Monoverticillus-Spira, Series white to gray. When the organism was shakecultured in a wheat flour medium, an antibacterial antibiotic with limited antitumor activity was isolated from the culture filtrate and a tetraene antibiotic from the mycelial cake. The antibacterial antibiotic proved to be closely related to or identical with BA-180265 A (kanchanomycin) reported by Liu et al. in 1963.
The MIC of 48 antibiotics and other antifungal agents was established for the wild type and six mutants of Blastocladiella emersonii, as well as B. britannica, B. simplex, B. cystogena, and the related Allomyces macrogynus. Meiospores and mitospores of A. macrogynus differed from RS and OG spores of B. entersonii primarily in their responses to tetracycline, trichomycin, mitomycin C, antimycin A, and actinomycin, as well as bis(dimethylthiocarbamoyl) disulfate (T-l) and acrinavin (T-13). The four wild type species of Blastocladiella differed from one another primarily in their responses to mitomycin C, actinomycin S, chloramphenicol, endomycin, chlortetracycline, and trichomycin, as well as pentachloronitrobenzene (T-7), 2, 4-dichloro-6-(2-chloranylyno)-S-triazine (T-8), 2, 2/-methylene bis(3, 4, 6 trichlorophenol) (T-9), 3, 4, 4'-trichlorocarbanilide (T-4), malachite green (T-12), and T-13. The wildtype B. emersonii differed from its albino mutants primarily in its response to antimycin A, T-4, and (T-8). The Blastocladiaceae were also compared with two yeasts and Staphylococcus aureus in their response to various toxicants.
A new streptomycete metabolite sphydrofuran was isolated from the culture filtrate of the strain MC41-M1 and MC340-A1 by a chemical screening method using Ehrlich reagent. Sphydrofuran was an acid-unstable substance and the structure of an acid-hydrolysis product was determined as 2-methyl- .4-(l-glyceryl) furan.
The structure of a new streptomycete metabolite sphydrofuran was determined as an anomeric mixture of 3, 4, 5'-trmydroxy-S'-methyl-2, 3-spirobi(tetrahydrofuran) (A1 and A2) which is brought into an equilibrium mixturewith trans-3, cis-4-dihydroxy-trans-2-hydroxymethyl-2-acetonyl (tetrahydrofuran)(A3) in some solvents.
The fermentation conditions for the production of validamycin by Streptomyces hygroscopicus var. limoneus No. T-7545 were studied. Validamycins A and B showed no antimicrobial activity on agar media against bacteria, yeasts and fungi, but caused an abnormal branching at the tips of the hyphae of Pellicularia sasakii. Although they were inactive in vitro, validamycins A and B controlled the sheath blight of rice plants and the damping off of cucumber seedlings in green house tests. Validamycin A was effective against the sheath blight at a concentration of 30ppm. Both antibiotics showed low toxicity to plants, fishes and mice.
Validamycin was found to cause an abnormal branching at the tips of the hyphae of Pellicularia sasakii under specific conditions. By application of this phenomenon, an agar dilution method, "dendroid-test method", was established. In another method called the "reversed layer method", agar plates inoculated with P. sasakii are incubated for 40 to 45 hours, then covered with more agar medium and paper disks dipped in the sample solution are applied on the surface. After overnight incubation the diameters of the inhibition zones are measured.
Newantibiotics named validamycins A and B, active against the sheath blight of rice plants, were isolated from the culture nitrate of Streptomyces hygroscopicus var. limoneus. Validamycins A and B are water-soluble, glucosecontaining basic antibiotics, and with molecular formulae of C20H3337NO1314 and C20H3337NO1415, respectively.
The structure of thioformin, a new acidic antibiotic substance obtained by removing cupric ion from antibiotic YC 73, was shown to be N-methyl-N-thioformylhydroxylamine by degradative and synthetic studies. Numerous metal complexes of thioformin, including the cupric (antibiotic YC 73 itself) and ferric complexes, were also synthesized and characterized.
N-Substituted thioformylhydroxylamine derivatives represented by the general formula RHO-N-C-SH were synthesized and examined for antimicrobial activity. These compounds were analogues of an antibiotic thioformin which was confirmed to be N-methyl-N-thioformylhydroxylamine.