Determination of functional domains and topology model of membrane-bound Delta-6 desaturase enzyme from Mortierella alpina

Ashaar Ghadim, Esmat; Gharanjik, Shahrokh; Baghban Kohnerouz, Bahram

Determination of functional domains and topology model of membrane-bound Delta-6 desaturase enzyme from Mortierella alpina

Document Type : Research Paper

Authors

¹ M.Sc. Student of Agricultural Biotechnology, Shahrood University of Technology, Shahrood, Iran.

² Assistant Professor, Department of Plant Breeding & Biotechnology, Shahrood University of Technology, Shahrood, Iran.

³ Associate Professor, Department of Plant Breeding & Biotechnology, University of Tabriz, Tabriz, Iran.

Abstract

Desaturase enzymes (EC: 1.14.19.3) catalyze dehydrogenation reactions and creates a double bond in the fatty acid chains. These enzymes classified into two groups, soluble and membrane each with different consensus motifs. Despite the Delta-6 desaturase is a key enzyme in the biosynthesis of unsaturated fatty acids but due to lack of structural information of membrane-bound desaturase, it's three-dimensional and crystal structure has not been determined. Mortierella alpina is a rich source for production of unsaturated fatty acid arachidonic and has an active Delta-6 desaturases enzyme. The aim of this study was obtain encoding sequences of Delta-6 desaturase gene, and determination of functional domains using comparative analysis and molecular model and propose a membrane topology model for this enzyme. Thus, after extraction of total RNA and cDNA synthesis using gene specific primers, PCR product was cloned into pBlueScriptSK+ vector and then sequenced. Based on bioinformatics analysis by Swissmodel, Predict and Phobius servers presence of functional domains cytochrome b5 carrying motif (HPGG), three His-box motifs and transmembrane regions were identified. Then we proposed a membrane topology model for the Delta-6 desaturase enzyme.

Keywords

20.1001.1.22520783.1395.6.15.2.8

Main Subjects

Molecular Genetics and Genetic Engineering

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