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Biomedical subjects

L A Mitscher

Publications and source records attributed to L A Mitscher.

At least 91 records · Page 5Linked to original sources
PubMed1967

Isolation of the bromo analogue of caldariomycin from Caldariomyces fumago.

When bromide ion was substituted for chloride in the growth medium of Caldariomyces fumago, a new substance was produced. It was isolated by solvent extraction and purified by alumina chromatography. Examination of the physicochemical properties of the substance led to its identification as the bromo analogue of the normal metabolite, caldariomycin. Thus, biological substitution of bromine for chlorine has been demonstrated in the metabolic formation of a purely aliphatic secondary mold metabolite.

Anti-Bacterial Agents↗
PubMed1967

LL-A491, a monazomycin-like antibiotic.

A new antibiotic, designated LL-A491, was isolated by butanol extraction and crystallization from beers of an unidentified streptomycete, Lederle culture A491. LL-A491 was primarily active against gram-positive bacteria and was related to monazomycin. A tentative molecular formula of C(72+/-2) H(144+/-8) O(25+/-1) N for the antibiotic, based on analyses of the crystalline hydrochloride, picrate, and picrolonate salts, is considerably larger than that proposed for monazomycin, from which LL-A491 was not differentiated by paper chromatography. Analysis of the amorphous polyacetate ester suggested 15 to 16 acetylable groups. Upon hydrolysis, LL-A491 liberated ammonia and a reducing sugar which appeared to be mannose. LL-A491 was dextrorotatory, [alpha](D) (25) + 14 degrees , and exhibited only end absorption in the ultraviolet region.

Ammonia↗