Search PubMed⌕ Search

Biomedical subjects

K Bloch

Publications and source records attributed to K Bloch.

At least 91 records · Page 5Linked to original sources
PubMed1973

Fatty acyl-coenzyme A elongation in brain of normal and quaking mice.

Microsomal enzyme systems from mouse brain that catalyze, respectively, the elongation of palmitoyl-coenzyme A (palmitoyl-CoA), stearoyl-CoA, or arachidyl-CoA appear and reach maximal activity at different times after birth of the animal. A specific C(20)-CoA elongating system exists in mouse brain in addition to the previously recognized C(16)-CoA and C(l8)-CoA elongating enzymes. The C(20)-CoA elongation system is severely reduced in the mutant quaking mouse.

Age Factors↗
PubMed1973

Complex formation between mycobacterial polysaccharides and fatty acyl-CoA derivatives.

The mycobacterial polysaccharides MMP and MGLP, which contain numerous O-methyl-sugar residues, markedly stimulate fatty acid synthesis catalyzed by a multienzyme complex from Mycobacterium phlei [Ilton, M. et al. (1971) Proc. Nat. Acad. Sci. USA 68, 87-91]. When aqueous solutions containing MMP or MGLP and palmitoyl-CoA were chromatographed on Sephadex G-75 under conditions that widely separate the individual components, polysaccharide and fatty acyl-CoA were eluted in a single peak, indicating formation of a molecular complex. Similarly, the mycobacterial polysaccharides associate with the CoA derivatives of C(18), C(20), and C(22) acids to yield complexes containing maximally 1 mol of fatty acyl-CoA per mol of polysaccharide. The formation of these novel complexes may result from hydrophobic interactions between the paraffin chains of the acyl-CoA derivatives and O-methyl-sugar residues of the polysaccharides.

Chromatography, Gel↗
PubMed1973

Inhibition of lipid synthesis in Escherichia coli cells by the antibiotic cerulenin.

The antibiotic cerulenin markedly inhibits the growth of Escherichia coli. The effects of the antibiotic on cellular syntheses were studied by measuring the incorporation of labeled precursors into lipids and macromolecules. During the first 40 min after the addition of cerulenin to a culture of growing cells, lipid synthesis was inhibited more than 90% and ribonucleic acid and deoxyribonucleic acid synthesis about 25%, whereas protein synthesis was not affected. At later periods after cerulenin addition (1 to 2 h), the inhibition of cell growth and of lipid and protein synthesis was complete. Upon removal of cerulenin from the culture, growth was restored and lipid synthesis resumed more rapidly than did the synthesis of protein. Addition of both palmitate and oleate, but not of either fatty acid alone, reversed the inhibition of growth by cerulenin. These findings support the conclusion that the antibiotic effects of cerulenin are due to a specific inhibition of fatty acid synthesis.

Anti-Bacterial Agents↗