Biosynthesis of vitamin B12: structure of precorrin-6x octamethyl ester.
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چکیده
منابع مشابه
Biosynthesis of vitamin B12: isolation of precorrin-6x, a metal-free precursor of the corrin macrocycle retaining five S-adenosylmethionine-derived peripheral methyl groups.
delta-Aminolevulinic acid and trimethylisobacteriochlorin are converted by cell-free protein preparations from Pseudomonas denitrificans into a metal-free pigment, precorrin-6x. This pigment, which accumulates when the cell-free system lacks NADPH, can be enzymically converted in high yield (greater than 50%) into hydrogenobyrinic acid by the complete enzyme preparation. Double-labeling experim...
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Although radioassays for vitamin B12 with use of any of several binding proteins have been available for many years, a radioimmunoassay for B12 has not been reported. We describe here such a radioimmunoassay, incorporating, for the first time, a radioiodinated tyrosine methyl ester of B12 as the radioactive tracer. Polypropylene tubes are coated with antiserum raised in a rabbit against B12/bov...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1990
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.87.22.8800