Linked Life Data

10956019

Source:http://linkedlifedata.com/resource/pubmed/id/10956019

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
33
pubmed:dateCreated
2000-9-12
pubmed:abstractText
A novel thrombin-like enzyme (named contortrixobin) has been purified to homogeneity from the venom of Agkistrodon contortrix contortrix by affinity chromatography on arginine-Sepharose, anionic exchange chromatography, and HPLC. The complete amino acid sequence has been determined by Edman degradation and by mass spectral analysis of peptides generated by enzymatic cleavage. A microheterogeneity at the level of residue 234 has been detected, as demonstrated by peptides differing for the occurrence of Pro234 ( approximately 85%) or Asp234 ( approximately 15%). Contortrixobin (i) has six disulfide bonds whose sequence positions have been determined by mass spectrometry and (ii) does not contain carbohydrates in its structure. As expected, the 234 residue sequence of contortrixobin exhibits strong homology with snake venom serine proteases acting on either fibrinogen or other blood coagulation components. The interaction of contortrixobin with chromogenic substrates indicates a higher specificity for arginine over lysine in the primary subsite and a faster attack to ester than amides. The hydrolytic activity of contortrixobin is strongly inhibited by diisopropyl fluorophosphate and to a less extent by phenylmethylsulfonyl fluoride, benzamidine, and 4', 6-diamidino-2-phenylindole; hirudin (a specific alpha-thrombin inhibitor) as well as basic pancreatic trypsin inhibitor has a small effect on contortrixobin's catalytic properties. Contortrixobin (i) preferentially releases fibrinopeptide B from human fibrinogen, (ii) activates blood coagulation Factors V and XIII with a rate 250-500-fold lower than human alpha-thrombin, and (iii) does not induce thrombocyte aggregation, intracytoplasmatic calcium ion increase in platelets, and activation of Factor VIII. Evidence for biorecognition properties different from thrombin is also reported.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10294-308
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10956019-Agkistrodon, pubmed-meshheading:10956019-Amino Acid Sequence, pubmed-meshheading:10956019-Animals, pubmed-meshheading:10956019-Disulfides, pubmed-meshheading:10956019-Endopeptidases, pubmed-meshheading:10956019-Fibrinogen, pubmed-meshheading:10956019-Fibrinopeptide A, pubmed-meshheading:10956019-Fibrinopeptide B, pubmed-meshheading:10956019-Humans, pubmed-meshheading:10956019-Hydrolysis, pubmed-meshheading:10956019-Molecular Sequence Data, pubmed-meshheading:10956019-Protease Inhibitors, pubmed-meshheading:10956019-Sequence Analysis, Protein, pubmed-meshheading:10956019-Serine Endopeptidases, pubmed-meshheading:10956019-Snake Venoms, pubmed-meshheading:10956019-Substrate Specificity, pubmed-meshheading:10956019-Thrombin, pubmed-meshheading:10956019-Viper Venoms
pubmed:year
2000
pubmed:articleTitle
A novel venombin B from agkistrodon contortrix contortrix: evidence for recognition properties in the surface around the primary specificity pocket different from thrombin.
pubmed:affiliation
Department of Biochemical Sciences, University of Rome "La Sapienza", Italy. gino.amiconi@uniroma1.it
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't