Báo cáo Y học: Isolation, enzymatic properties, and mode of action of an exo-1,3-b-glucanase from Trichoderma viride
An exo-1,3-b-glucanase has been isolated from cultural filtrate of Trichoderma viride AZ36. The N-terminal sequence of the purified enzyme (m ¼ 61 ^ 1 kDa) showed no significant homology to other known glucanases. The 1,3-b-glucanase displayed high activity against laminarins, curdlan, and 1,3-b-oligoglucosides, but acted slowly on 1,3-1,4-b-oligoglucosides. No significant activity was detected against high molecular mass 1,3-1,4-bglucans. The enzyme carried out hydrolysis with inversion of the anomeric configuration. Whereas only glucose was released from the nonreducing terminus during hydrolysis of 1,3-b-oligoglucosides, transient accumulation of gentiobiose
was observed during hydrolysis of laminarins....9 trang
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Báo cáo Y học: Assignment of molecular properties of a superactive coagulation factor VIIa variant to individual amino acid changes
Eur. J. Biochem. 269, 5950–5955 (2002) Ó FEBS 2002
doi:10.1046/j.1432-1033.2002.03323.x
The most active factor VIIa (FVIIa) variants identified to
date carry concurrent substitutions at positions 158, 296and
298 with the intention of generating a thrombin-mimicking
motif, optionally combined with additional replacements
within the protease domain [Persson, E., Kjalke, M. &
Olsen, O. H. (2001)Proc. Natl Acad. Sci. USA98, 13583–
13588]. Here we have characterized variants of FVIIa
mutatedat one or twoof these positions toassess the relative
importance of the individual replacements.
Assignment of molecular properties of a superactive coagulation factor VIIa variant to individual amino acid changes
Egon Persson1 and Ole H. Olsen2
1
Haemostasis Biology and 2Medicinal Chemistry Research IV, Novo Nordisk A/S,...6 trang
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