当前位置： SCI文献检索 > BMC BIOTECHNOLOGY期刊下所有文献 > Identification of residues important for the activity of aldehyde-deformylating oxygenase through investigation into the structure-activity relationship.

Identification of residues important for the activity of aldehyde-deformylating oxygenase through investigation into the structure-activity relationship.

Abstract：

BACKGROUND:Aldehyde-deformylating oxygenase (ADO) is a key enzyme involved in the biosynthetic pathway of fatty alk(a/e)nes in cyanobacteria. However, cADO (cyanobacterial ADO) showed extreme low activity with the k cat value below 1 min-1, which would limit its application in biofuel production. To identify the activity related key residues of cADO is urgently required. RESULTS:The amino acid residues which might affect cADO activity were identified based on the crystal structures and sequence alignment of cADOs, including the residues close to the di-iron center (Tyr39, Arg62, Gln110, Tyr122, Asp143 of cADO-1593), the protein surface (Trp 178 of cADO-1593), and those involved in two important hydrogen bonds (Gln49, Asn123 of cADO-1593, and Asp49, Asn123 of cADO-sll0208) and in the oligopeptide whose conformation changed in the absence of the di-iron center (Leu146, Asn149, Phe150 of cADO-1593, and Thr146, Leu148, Tyr150 of cADO-sll0208). The variants of cADO-1593 from Synechococcus elongatus PCC7942 and cADO-sll0208 from Synechocystis sp. PCC6803 were constructed, overexpressed, purified and kinetically characterized. The k cat values of L146T, Q49H/N123H/F150Y and W178R of cADO-1593 and L148R of cADO-sll0208 were increased by more than two-fold, whereas that of R62A dropped by 91.1%. N123H, Y39F and D143A of cADO-1593, and Y150F of cADO-sll0208 reduced activities by ≤ 20%. CONCLUSIONS:Some important amino acids, which exerted some effects on cADO activity, were identified. Several enzyme variants exhibited greatly reduced activity, while the k cat values of several mutants are more than two-fold higher than the wild type. This study presents the report on the relationship between amino acid residues and enzyme activity of cADOs, and the information will provide a guide for enhancement of cADO activity through protein engineering.

journal_name

BMC Biotechnol

journal_title

BMC biotechnology

authors

Wang Q,Bao L,Jia C,Li M,Li JJ,Lu X

doi

10.1186/s12896-017-0351-8

subject

Has Abstract

pub_date

2017-03-16 00:00:00

pages

issue

issn

1472-6750

pii

10.1186/s12896-017-0351-8

journal_volume

pub_type

杂志文章

在线工具

Identification of residues important for the activity of aldehyde-deformylating oxygenase through investigation into the structure-activity relationship.