Herein, we applied a community genomic approach using a naphthalene-enriched community (CN1) to isolate a versatile esterase (CN1E1) from the α/β-hydrolase family. The protein shares low-to-medium identity (≤ 57%) with known esterase/lipase-like proteins. The enzyme is most active at 25-30°C and pH 8.5; it retains approximately 55% of its activity at 4°C and less than 8% at ≥ 55°C, which indica...

By using the I-naphthyl acetate assay system, we found that xenobiotics can induce increased esterase activity in cultures of the yeast-like symbiont, Symbioraphrina kochii Jurzitza ex. W. Gams and v. Arx, of the cigarette beetle, Lasioderma serricome L.. The activities expressed as percent of solvent control are as follows: flavone, 184.2% ; griseofulvin, 115.8 ~~ ; cis()-p-pinene, 111.4% ; an...

In the present work, we describe for the first time the specific role of cutinase on surface modification of cellulose acetate fibers. Cutinase exhibits acetyl esterase activity on diacetate and triacetate of 0.010 U and 0.007 U, respectively. An increase on the hydroxyl groups at the fiber surface of 25% for diacetate and 317% for triacetate, after a 24 h treatment, is estimated by an indirect...

Using either hexazotized pararosaniline or new fuchsin as coupling agents, we investigated the ultrastructural localization of alpha-naphthyl acetate esterase (ANAE) activity in guinea pig bone marrow and peritoneal exudates, and in human peripheral blood cells. DFP-inhibitable ANAE activity was present on the cell surface of lymphocytes, monocytes, macrophages, neutrophils, eosinophils, basoph...

Exposure of bovine pulmonary-arterial endothelial cells to the oxidant lipid t-butyl hydroperoxide (t-Bu-OOH) increases cell-membrane-associated phospholipase A2 (PLA2) activity and stimulates arachidonic acid (AA) release. To test the hypothesis that a membrane-associated serine esterase plays an important role in activating PLA2, the present study was undertaken. In addition to increasing PLA...

Resorufin acetate is a very good substrate for sheep liver cytosolic aldehyde dehydrogenase, both from the point of view of practical spectrophotometry and in terms of information provided about the nature of the catalysis shown by this enzyme. p-Nitrophenyl (PNP) acetate competes against resorufin acetate for the enzyme's active site (although relatively weakly as the latter substrate has the ...

Pneumococcal neuraminidase is a key enzyme for sequential deglycosylation of host glycans, and plays an important role in host survival, colonization, and pathogenesis of infections caused by Streptococcus pneumoniae. One of the factors that can affect the activity of neuraminidase is the amount and position of acetylation present in its substrate sialic acid. We hypothesised that pneumococcal ...

Two novel esterase genes, est2L and est4L, were identified from a previously constructed metagenomic library derived an oil-polluted mud flat sample. The encoded Est2L Est4L composed of 839 267 amino acids, respectively, without signal peptides. was unique fusion type protein two domains: domain the CzcO superfamily, associated with cationic diffusion promoter CzcD, acetylesterase belonging to ...

Influenza C virus (strain C/Johannesburg/1/66) was grown, harvested, purified and used as source for the enzyme O-acetylesterase (N-acyl-O-acetylneuraminate O-acetylhydrolase; EC 3.1.1.53). This activity was studied and characterized with regard to some new substrates. The pH optimum of the enzyme is around 7.6, its stability at different pH values shows a result similar to that of the pH optim...