China
Africa
Explore chapters and articles related to this topic
Dopaminergic Prodrugs
Published in M.D. Francesco Amenta, Peripheral Dopamine Pathophysiology, 2019
Cesare Casagrande, Francesco Santangelo
The selective cleavage of γ-glutamyldopamine by γ-glutamyltranspeptidase was demonstrated in an in vitro experiment with a partially purified preparation from canine renal cortex;174 the cleavage was potentiated by glycylglycine, a known acceptor for the γ-glutamyl moiety in reaction mediated by the enzyme and blocked by a known inhibitor, i.e., a combination of d,l-serine and sodium tetraborate. On the other hand, in contrast to N-l-alanyldopamine, γ-glutamyldopamine was not cleaved by crystalline arylamidase from hog kidney. The localization of the cleaving activity in the particulate fraction of cortical homogenates was consistent with the known localization of the enzyme in the proximal tubules and the loop of Henle and appeared to exclude the involvement of γ-glutamylcyclotransferase, a soluble enzyme.
Intracellular Peptide Turnover: Properties and Physiological Significance of the Major Peptide Hydrolases of Brain Cytosol
Published in Gerard O’Cuinn, Metabolism of Brain Peptides, 2020
In 1965, Ellis and Perry separated two enzymes from bovine pituitary which they termed as arginyl arylamidase and lysyl arylamidase119. The arginyl arylamidase is likely identical to an enzyme now named arginyl aminopeptidase (EC 3.4.11.6) also known as aminopeptidase B. The lysyl arylamidase, characterized by its ability to cleave the substrate Lys-p-nitroanilide, could also cleave the p-nitroanilide derivatives of Arg, Phe, Met and Leu. This enzyme, found mainly in the cytosol, was reported to have a requirement for thiol compounds and to be inhibited by EDTA. A distinguishing feature was its strong inhibition by puromycin. An arylamidase was partially purified from bovine brain in 1969 by Brecher and Suszkiw120. These investigators further purified the enzyme and demonstrated that the arylamidase was an aminopeptidase, although it did not hydrolyze simple di- and tri-peptides121. Their preparation although highly purified was not homogeneous. In 1977 Hayaishi and Oshima described the purification of the monkey brain enzyme to electrophoretic homogeneity122. This enzyme subsequently studied by many investigators is referred to in the literature as arylamidase or more commonly as puromycin-sensitive aminopeptidase. It is now officially designated as cytosol alanyl aminopeptidase (c-AAP). c-AAP has generated much interest since it is the major enkephalin-degrading aminopeptidase in brain123–129. In fact in terms of total activity it is the major brain aminopeptidase. An antiserum prepared against c-AAP inhibited essentially all of the Ala-naphthylamide hydrolyzing activity of brain130.
Biologically rapid synthesis of silver nanoparticles by Sphingobium sp. MAH-11T and their antibacterial activity and mechanisms investigation against drug-resistant pathogenic microbes
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2020
Shahina Akter, Md. Amdadul Huq
The 16Sr RNA gene sequence of isolated strain MAH-11 was 1351 bp and the sequence of 16Sr RNA gene has been submitted to NCBI for GenBank accession number (MH553056). According to the EzTaxon-e server, strain MAH-11 showed highest sequence similarity with Sphingobium quisquiliarum P25T (98.1%). The phylogenetic analysis using neighbour-joining tree indicated that strain MAH-11 is clustered and clearly grouped within the genus Sphingobium (Figure 1). The biochemical characteristics of isolated strain MAH-11 carried out using API ZYM and API 20 NE are shown in Table 1. The strain MAH-11 was positive for following enzyme activities: valine arylamidase, cystine arylamidase, leucine arylamidase, alkaline phosphatase, acid phosphatase, β-galactosidase, β-glucosidase, naphthol-AS-BI-phosphohydrolase and α-chymotrypsin. Weekly positive for following enzyme activities: lipase (C-14), α-glucosidase, esterase (C4), esterase lipase (C8) and trypsin, but negative for N-acetyl-β-glucosaminidase, α-galactosidase, α-fucosidase, α-mannosidase and β-glucuronidase (API ZYM). Tests for glucose fermentation, nitrate reduction and indole production are negative. Only D-glucose is utilized as sole carbon source, but other compounds such as L-arabinose, N-acetyl-glucosamine, D-mannitol, D-maltose, gluconate, D-mannose, malic acid, phenylacetic acid, adipic acid, triosodium citrate or capric acid are not utilized as sole carbon source (API 20 NE).
Association between Streptococcus gallolyticus and colorectal cancer in Mansoura University hospitals
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Heba E. Eldegla, Mohamed Abdel-Wahhab, Dalia Moemen
S. gallolyticus was identified by colony morphology; black-colored colonies caused by esculin hydrolysis as illustrated in Figure 1, Gram stained films and biochemical reactions including catalase and pyrrolidonyl arylamidase (Becton, Dickinson and company, USA).