Although C–N bonds are ubiquitous in natural products, pharmaceuticals and agrochemicals, biocatalysts forging these with high atom-efficiency enantioselectivity have been limited to a few select enzymes. In particular, ammonia lyases emerged as powerful catalysts access bond formation via hydroamination. However, the use of is rather restricted due their narrow synthetic scope. Herein, we repo...

Phenylalanine ammonia-lyase activity increased rapidly beginning 2 h after inoculation with Phytophthora megasperma (Drechs.) f.sp. glycinea (Hildeb.) Kuan & Erwin race 1 in unwounded hypocotyls of soybean cv. Harosoy 63 (resistant) but did not change significantly in cv. Harosoy (susceptible). Small increases in phenylalanine ammonia-lyase activity also were caused by wounding. Activity increa...

ammonia is a toxic material for mammalians. it is detoxificated and converted to urea in the urea cycle in liver. each defect in the urea cycle cause increase in blood ammonia level. ornithine transcarbamylase enzyme (otc) is the second enzyme in the urea cycle that exists in mitochondria. otc deficiency is the most common hereditary disorder in the urea cycle. in this study, 45 hyper ammonia p...

Pathways of ammonia assimilation into glutamic acid and alanine in Bacillus polymyxa were investigated by "N NMR spectroscopy in combination with measurements of the specific activities of glutamate dehydrogenase, glutamine synthetase, glutamate synthase, alanine dehydrogenase, and glutamic-alanine transaminase. Ammonia was found to be assimilated into glutamic acid predominantly by NADPH-depen...

The synthesis of urocanic acid by histidine ammonia-lyase in guinea-pig epidermis was investigated in various ways. 1. In epidermal homogenates the enzyme obeys Michaelis-Menten kinetics and shows marked dependence of its activity of pH, such that below pH 6 it is inactive. 2. Part-thickness skin samples cultured with radioactive histidine do not accumulate detectable radioactive urocanic acid ...