Linked Life Data

18337701

Source:http://linkedlifedata.com/resource/pubmed/id/18337701

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-3-13
pubmed:abstractText
Thermostable esterase gene was cloned (Est-AF) from extremophilic microorganisms, Archaeoglobus fulgidus DSM 4304. The protein analysis result showed that Est-AF is monomer with total 247 amino acids and molecular weight of estimated 27.5 kDa. It also showed repeating units G-X-S-X-G (GHSLG) (residues 86 approximately 90) which is reported as active site of known esterases, and the putative catalytic triad composed of Ser88, Asp198 and His226. The esterase activity test with various acyl chain length of rho-nitrophenol resulted that Est-AF showed highest specific activity with rho-nitrophenylbutyrate (pNPC4) and rapidly decrease with rho-nitrophenyl ester contain more than 8 carbon chain. These results represent that cloned enzyme is verified as a carboxylesterase but not a lipase because esterase activity is decreased with rho-nitrophenyl ester contains more than 8 carbon chains but lipase activity does not affected with carbon chain length. Optimum temperature of esterase reaction with rho-nitrophenylbutyrate (pNPC4) was 80 degrees C. When ketoprofen ethyl ester was used as a substrate, activity of Est-AF showed the highest value at 70 degrees C, and 10% of activity still remains after 3 h of incubation at 90 degrees C. This result represents Est-AF has high thermostability with comparison of other esterases that have been reported. However, Est-AF showed low enantioselectivity with ketoprofen ethyl ester. Optimum pH of Est-AF is between pH 7.0 and pH 8.0. Km value of ketoprofen ethyl ester is 1.6 mM and, Vmax is 1.7 micromole/mg protein/min. Est-AF showed similar substrate affinity but slower reaction with ketoprofen ethyl ester compare with esterase from mesophilic strain P. fluorescens.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1225-8873
pubmed:author
pubmed:issnType
Print
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
100-7
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Cloning and characterization of thermostable esterase from Archaeoglobus fulgidus.
pubmed:affiliation
Department of Molecular Science and Technology, College of Engineering, Ajou University, Suwon 443-749, Republic of Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't