Amplification And Analysis Of Polyketide Synthase Gene From Marine Actinomycetes

Polyketide synthase is a complex multi enzyme system which catalyzes the biosynthesis of polyketide.In this paper,marine actinomycetes were screened from Dalian sea area,and the polyketide synthase gene fragment was amplified from genomic DNA and analyzed by Bioinformatics,We hope to provide a theoretical basis for the application of polyketide synthase in structure and function.The main results are as follows:1.Screening of marine actinomycetes from marine waters of Dalian,according to its culture mode and culture conditions and external morphological characteristics of the microscope observation,and a preliminary identification of marine Streptomyces by reference to Berger's Handbook of bacterial identification,tentatively named Streptomyces sp LI.2.We designed a pair of polyketide synthase specific amplification primers,amplified fragment from L1 genomic DNA,sequencing results showed that the length of the inserted fragment is 307bp,reverse insertion into the pMD19-T carrier,consistent with the expected size of the target fragment.3.According to the primary structure analysis:the molecular formula of the expressed protein is C441H714N142O127S3,Molecular weight is10133.58Da.The instability index was 85.35,which belonged to the unstable protein.GRAVY is-0.233,belonging to hydrophilic protein.According to the analysis of the two level structure:Alpha helical structure accounted for 4.08%,Extended chain accounted for 22.45%,Irregular curl accounted for 3.47%.