scispace - formally typeset
Search or ask a question
Topic

Esterase

About: Esterase is a research topic. Over the lifetime, 7622 publications have been published within this topic receiving 168270 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: It is proposed that the patatin-like hydrolase is involved in lipid body mobilization as maximal amounts of the protein were found at an early stage of mobilization and confined to lipid bodies.

59 citations

Journal ArticleDOI
TL;DR: Phylogenetic analysis revealed that the lipolytic protein EstD2 may be a member of a novel family oflipolytic enzymes and suggested that the other hypothetical protein homologs of EstD 2 might also be members of this novel family.
Abstract: Soil metagenome constitutes a reservoir for discovering novel enzymes from the unculturable microbial diversity. From three plant rhizosphere metagenomic libraries comprising a total of 142,900 members of recombinant plasmids, we obtained 14 recombinant fosmids that exhibited lipolytic activity. A selected recombinant plasmid, pFLP-2, which showed maximum lipolytic activity, was further analyzed. DNA sequence analysis of the subclone in pUC119, pELP-2, revealed an open reading frame of 1,191 bp encoding a 397-amino-acid protein. Purified EstD2 exhibited maximum enzymatic activity towards p-nitrophenyl butyrate, indicating that it is an esterase. Purified EstD2 showed optimal activity at 35 °C and at pH 8.0. The K m and K cat values were determined to be 79.4 μM and 120.5/s, respectively. The esterase exhibited an increase in enzymatic activity in the presence of 15% butanol and 15% methanol. Phylogenetic analysis revealed that the lipolytic protein EstD2 may be a member of a novel family of lipolytic enzymes. Several hypothetical protein homologs of EstD2 were found in the database. A hypothetical protein from Phenylobacterium zucineum HLK1, a close homolog of EstD2, displayed lipolytic activity when the corresponding gene was expressed in Escherichia coli. Our results suggest that the other hypothetical protein homologs of EstD2 might also be members of this novel family.

59 citations

Journal ArticleDOI
TL;DR: A plant cell suspension culture of Alfalfa was grown in a bioreactor using a batch procedure and the cytoplasmic esterase activity was conclusively found to be correlated to cell viability assessed with the membrane integrity test using the trypan blue dye.
Abstract: A plant cell suspension culture of Alfalfa (Medicago sativa L.) was grown in a bioreactor using a batch procedure. The cytoplasmic esterase activity (EC 3.1) was extracted from the cells and measured during cultivation using fluorescein diacetate as the fluorogenic substrate. This enzymatic activity was conclusively found to be correlated to cell viability assessed with the membrane integrity test using the trypan blue dye. This new viability determination method is convenient, simple and can be reproduced because: (1) the difficult step of counting the cells when using the trypan blue exclusion method is avoided and (2) the esterase activity level per viable cell constituted of numerous enzymes depends on cell viability but is independent of cellular metabolism.

59 citations

Journal ArticleDOI
TL;DR: Analysis of the predicted amino acid sequences for the PueB, PueA, and other polyurethanase enzymes and similar lipase enzymes suggested that they have evolved from lipases, and are not derived from a single source.

59 citations

Journal ArticleDOI
TL;DR: Inhibition studies with known protease inhibitors revealed that poliovirus protease 2A is probably a sulfhydryl protease, which was optimal near neutral pH and had an extremely short half-life at physiological temperatures.
Abstract: The purification of poliovirus protease 2A from infected cells by a functional assay is described. A small synthetic peptide was cleaved specifically by an esterase present in poliovirus-infected cells. Since the enzyme proved extremely unstable in crude extracts a rapid and efficient purification procedure had to be developed. By treatment with different detergents followed by high-speed centrifugation, the esterase activity was separated from inactivating cellular enzymes and was solubilized. Purification to more than 90% homogeneity could be achieved by a single chromatography step, namely, by gel filtration through Superose 12 under fast-protein liquid chromatography conditions. The esterase activity was associated with a protein of 17,000 daltons and copurified with poliovirus protein 2A. Furthermore, antibodies to 2A specifically precipitated the esterase activity. Thus, the esterase was identified as poliovirus protease 2A. Inhibition studies with known protease inhibitors revealed that 2A is probably a sulfhydryl protease. Of the metal ions tested, only zinc exerted significant inhibitory effects. The esterase activity was optimal near neutral pH and had an extremely short half-life at physiological temperatures.

59 citations


Network Information
Related Topics (5)
Enzyme
32.8K papers, 1.1M citations
90% related
Amino acid
124.9K papers, 4M citations
86% related
Peptide sequence
84.1K papers, 4.3M citations
82% related
Glutathione
42.5K papers, 1.8M citations
82% related
Protein subunit
33.2K papers, 1.7M citations
81% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202391
2022209
202183
2020112
2019107
2018129