The structural and functional studies of the non-stereospecific α-haloacid dehalogenase (DehE) from rhizobium sp. RC1

Abdul Hamid, Azzmer Azzar and Wong , Ee Lin and Joyce-Tan, Kwee Hong and Shamsir, Mohd Shahir and Tengku Abdul Hamid, Tengku Haziyamin and Huyop, Fahrul Zaman (2013) The structural and functional studies of the non-stereospecific α-haloacid dehalogenase (DehE) from rhizobium sp. RC1. In: Biomicroworld2013, 2-3 October 2013, Madrid Spain.

Preview	PDF - Published Version Download (100kB) | Preview
Preview	PDF Download (192kB) | Preview
	PDF Restricted to Registered users only Download (39MB) | Request a copy

Abstract

Environmental pollution caused by the abundance of xenobi otic compounds in nature. For instance, synthetically halogenated compounds released from chemical industry we re proven harmful to our health and environment. However, α-haloacid dehalogenases could catalysed the removal of halides from organic haloalkanoic acids and of interest for bioremediation. This study presents the first structural conformations and important residues of the non-stereospecific α-haloacid dehalogenase, DehE from Rhizobium sp. RC1. The enzyme was modeled using ‘in silico’technique and crystal structure of DehI from Pseudomonas putida PP3 was used as a template since both of them gets high similiarity to each other. DehE consis ts of only helices motif and depicted active site showed that the binding orientiations of both D- and L-2-chlor opropionic acid by using substrate-docking analysis shared similar key binding residues among non-stereo specific α -haloacid dehalogenases. Twelve residues lining the active site has identified and some of them were verified using site-directed mutagenesis tests. Each residues was affected after mutation and Asp189 was proven to be as a catalytic residue for nucleophilic attack mechansim when its mutation resulted in total loss of activity. Three binding residues, Trp34, Phe37 and Ser188 were responsible for substrate recognition due to their mutati on had diminish activity of the enzyme to below 20%. These details will promote more protein engineering studies to α haloacid dehalogenases for future bioremediation and industrial applications.

Item Type:	Conference or Workshop Item (Full Paper)
Additional Information:	7089/37058
Uncontrolled Keywords:	DehE, Rhizobium sp. RC1, non-stereospecific dehalogenase, α-haloacid dehalogenase, binding residues, catalytic residues, site-directed mutagenesis
Subjects:	Q Science > Q Science (General)
Kulliyyahs/Centres/Divisions/Institutes (Can select more than one option. Press CONTROL button):	Kulliyyah of Science
Depositing User:	Dr Tengku Haziyamin Tengku Abd Hamid
Date Deposited:	29 Jan 2015 09:32
Last Modified:	08 Jul 2015 10:21
URI:	http://irep.iium.edu.my/id/eprint/37058

Actions (login required)

View Item