Abstract:
:The shape of the hydrophobic tunnel leading to the active site of Penicillium expansum lipase (PEL) was redesigned by single-point mutations, in order to better understand enzyme enantioselectivity towards naproxen. A variant with a valine-to-glycine substitution at residue 237 exhibited almost no enantioselectivity (E = 1.1) compared with that (E = 104) of wild-type PEL. The function of the residue, Val237, in the hydrophobic tunnel was further analyzed by site-directed mutagenesis. For each of these variants a significant decrease of enantioselectivity (E < 7) was observed compared with that of wild-type enzyme. Further docking result showed that Val237 plays the most important role in stabilizing the correct orientation of (R)-naproxen. Overall, these results indicate that the residue Val237 is the key amino acid residue maintaining the enantioselectivity of the lipase.
journal_name
Biotechnol Lettjournal_title
Biotechnology lettersauthors
Tang L,Su M,Chi L,Zhang J,Zhang H,Zhu Ldoi
10.1007/s10529-013-1405-1subject
Has Abstractpub_date
2014-03-01 00:00:00pages
633-9issue
3eissn
0141-5492issn
1573-6776journal_volume
36pub_type
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