Publication Date:
1993-10-15
Description:
Unlike most serine proteases of the chymotrypsin family, tissue-type plasminogen activator (tPA) is secreted from cells as an active, single-chain enzyme with a catalytic efficiency only slightly lower than that of the proteolytically cleaved form. A zymogenic mutant of tPA has been engineered that displays a reduction in catalytic efficiency by a factor of 141 in the single-chain form while retaining full activity in the cleaved form. The residues introduced in the mutant, serine 292 and histidine 305, are proposed to form a hydrogen-bonded network with aspartate 477, similar to the aspartate 194-histidine 40-serine 32 network found to stabilize the zymogen chymotrypsinogen.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Madison, E L -- Kobe, A -- Gething, M J -- Sambrook, J F -- Goldsmith, E J -- New York, N.Y. -- Science. 1993 Oct 15;262(5132):419-21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8211162" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Sequence
;
Aspartic Acid/chemistry
;
Base Sequence
;
Catalysis
;
Chymotrypsin/chemistry/metabolism
;
Enzyme Precursors/chemistry/*metabolism
;
Histidine/chemistry
;
Hydrogen Bonding
;
Kinetics
;
Molecular Sequence Data
;
Mutagenesis, Site-Directed
;
Mutation
;
Plasminogen/metabolism
;
Plasminogen Activator Inhibitor 1/metabolism
;
Serine/chemistry
;
Tissue Plasminogen Activator/chemistry/genetics/*metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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