Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P17174 (aspartate aminotransferase)
 14,872 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A recombinant B. megaterium strain was used for the heterologous production of a glucosyltransferase (dextransucrase). To better understand the physiological and metabolic responses of the host cell to cultivation and induction conditions, proteomic analysis was carried out by combined use of two-dimensional gel electrophoresis and mass spectrometry (2-DE/MS) for protein separation and identification. 2-DE method was optimized for the separation of intracellular proteins. Since the genome of B. megaterium is not yet available, peptide sequencing using peptide fragment information obtained from nanoelectrospray ionization quadrupole-time-of-flight tandem mass spectrometry (ESI-QqTOF MS/MS) was applied for protein identification. 167 protein spots were identified as 149 individual proteins, including most enzymes involved in the central carbon metabolic pathways and many enzymes related to amino acid synthesis and protein synthesis. Based on the results a 2-DE reference map and a corresponding protein database were constructed for further proteomic approaches on B. megaterium. For the first time it became possible to perform comparative proteomic analysis on B. megaterium in a batch culture grown on glucose with xylose induction for dextrasucrase production. No significant differences were observed in the expression changes of enzymes of the glycolysis and TCA cycle, indicating that dextransucrase production, which amounted to only 2 % of the entire protein production, did not impose notable metabolic or energetic burdens on the central carbon metabolic pathway of the cells. However, a short-term up-regulation of aspartate aminotransferase, an enzyme closely related to dextransucrase production, in the induced culture demonstrated the feasibility to use 2-DE method for monitoring dextransucrase production. It was also observed that under the cultivation conditions used in this study B. megaterium tended to channel acetyl-CoA into pathways of polyhydroxybutyrate production. No expression increases were found with cytosolic chaperones such as GroEL and DnaK during dextransucrase production and secretion, whereas a strong up-regulation of the oligopeptide-binding protein OppA was observed in correlation with an increased secretion of dextransucrase into the culture medium.
 ...
PMID:Proteome analysis of a recombinant Bacillus megaterium strain during heterologous production of a glucosyltransferase. 1592 46

In this study, we investigated the protective efficacy of extracellular polysaccharide from Cordyceps militaris (CEP-I) in liver and kidney and their regulating effect on gut microbiota against Pb-induced toxicity in vivo. The results indicated that CEP-I could reduce the Pb2+ content and organ index of liver and kidney in mice. Besides, biochemical analysis showed that CEP-I could improve the activity of glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum and organs, restore the physiological indexes of total protein (TP), albumin (ALB), blood urea nitrogen (BUN) and creatinine (CRE) in serum and decrease the enzyme activity of lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) in the liver and kidney of mice poisoned by Pb2+. This indicated that CEP-I has a protective effect on organs against damage in mice. In addition, CEP-I could regulate the expression of key proteins in the Nrf2 signaling pathway, including NF-E2-related factor 2 (Nrf2), Kelch-like ECH-associated protein-1 (Keap1), Heme oxygenase (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1). Furthermore, the intestinal flora analysis results indicated that CEP-I also has the capacity to regulate the intestinal flora imbalance caused by Pb2+ in poisoned mice. In conclusion, we hope that this study can provide theoretical basis for the treatment of tissue damage induced by Pb2+.
 ...
PMID:Using Cordyceps militaris extracellular polysaccharides to prevent Pb2+-induced liver and kidney toxicity by activating Nrf2 signals and modulating gut microbiota. 3303 Apr 75