In silico analysis of the deduced protein sequence of eugenol o-methyltransferase of Ocimum basilicum L.

Eugenol are the principal bioactive components of the defensive arsenal of the Ocimum species, which actas signal molecules among plants, humans, and microbes. The final stage in the biosynthesis ofphenylpropene, methyl eugenol is catalysis by eugenol O-methyltransferase (EOMT) enzyme. Thephylogenetic results indicated different EOMT form evolving from a single ancestral gene and resulting treewas classified into four clusters. ObEOMT was found associated with O. tenuiflorum. The ObEOMT proteinmolecular mass was predicted to be about ۴۰۲۳۶.۵۲ and the isoelectric point was predicted to be at ۵.۵۹calculated by the Online Computer pI/MW Tool (http://cn.expasy.org/tools). In addition, based onInterProScan tool and pfam database, the putative amino acids sequence revealed more homology withconserved active site consensus sequence at the N terminus of a variety of plant O-methyltransferases(MSLKCAIQLGIPDILHKHGRPMTLSQLLQSIPINKEKTQCFQRLMRALV) to mediate dimerisation andmethyltransferase of these proteins. As PROSITE motif search show, ObEOMT have four major motifs,ASN_GLYCOSYLATION (consisting of ۱۱۶ amino acids; N-{P}-[ST]-{P}), PKC_PHOSPHO_SITE(Protein kinase C phosphorylation site; [ST]-x-[RK]), CK۲_PHOSPHO_SITE (Casein kinase IIphosphorylation site; [ST]-x(۲)-[DE]), and MYRISTYL (N-myristoylation site; Ala, Ser, Thr, Cys, Asn andGly). According to conserved domain database, the ProDom and TrEMBL results showed ObEOMT proteinconsist of the essential domain, EQLLQAQVHVWNHMYAFANSMSLKCAIQLGIPDILHKHGRPMTLShas been specified in SAM-dependent O-methyltransferase class II-type profile. PSORT, signal P and TargetP analyses showed the presence of a GxG motif in the N-terminal region of ObEOMT amino acid sequence,which was not found in the protein localization signal peptide at the C-terminal region. Results revealed thatpredicted ObEOMT protein was a predominantly α-helical protein, which mainly consisted of alpha helices(۴۹.۳%) and random coils (۲۷.۲۲%), extended strands (۱۲.۹%), and ۳۷.۸% beta turns.

کلیدواژه ها:

eugenol O-methyltransferase (EOMT) ، phylogenetic analysis ، conserved domains ، catalytic domains ، motif prediction