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Biomedical subjects

H B White

Publications and source records attributed to H B White.

At least 91 records · Page 5Linked to original sources

Messenger RNA structure: compatibility of hairpin loops with protein sequence.

Examination of the amino acid sequences of human cytochrome c and the alpha-chain variant of human hemoglobin Constant Spring has revealed the possiblity for base-paired hairpin loops in the messenger RNA's for these proteins. A similar analysis of the bacteriophage R17 coat protein suggests an additional unobserved loop in the R17 RNA. If such loops are present in messenger RNA's generally, it would suggest that DNA has more than one stable base-paired conformation.

Amino Acid Sequence↗

Fatty acid synthetase activity in Mycobacterium phlei: regulation by polysaccharides.

The multienzyme complex from Mycobacterium phlei which catalyzes the synthesis of long chain fatty acids from acetyl-CoA and malonyl-CoA requires a heat-stable fraction (stimulating factor, SF) for activity. Fractionation of heat-treated M. phlei extracts affords two stimulatory subfractions, one of which (SF(2)) can be replaced by FMN. The other (SF(1)) is further separable into 3 polysaccharides (PS(I), PS(II), and PS(III)). PS(I) contains about 95% 3-O-methylmannose and 5% mannose; the sugar composition of PS(II) and PS(III) is about 55% 6-O-methylglucose and 45% glucose for both. Each of the three purified polysaccharides, in combination with FMN, substitutes for the crude stimulating factor. The polysaccharides exert their effect on the fatty acid synthetase by lowering the K(m) for acetyl-CoA about 50-fold.

Chromatography, Gel↗