Screening of bioethanol-relative genes from marine microbes

Abstract

◎ Background (or Objective) of This Study : Saccharification enzymes have highpotential for make bioactive compounds and bioethanol. Normally, bioethanolproduce through pre-treatment, saccharification, fermentation and distillation steps.Some of saccharification enzymes can use for bioethanol production such asbeta-glucanase, beta-glucosidase, alpha-amylase, xylanase and agarase. Theseenzymes can use for pre-treatment and saccharification. The ethanol fermentationmicrobes can convert to ethanol from mono-saccharides as glucose, xylose andgalactose. These mono-saccharide sources can make from starch, cellulose,laminarin, xylan, agar by enzymatic hydrolysis or acidic hydrolysis.◎ Methods : Samples were collected from coast of Chuuk state (Micronesia) andJeju (Republic of Korea) for isolate of saccharification enzyme producing bacteriafor bioethanol production. The enzymes were targeted as beta-glucosidase,beta-1,4-glucanase, beta-1,3-glucanase, beta-1,4-xylanase and agarase. Isolatedstrains were identified by 16s rRNA sequences. Based on the identified bacteria,primers were designed by compare with targeted genes of relative strains to genusor family or order from NCBI database. Genomic DNAs were isolated from eachstrains, and PCR were performed with different conditions. The PCR products werecloned into pGEM easy T vector and analyzed the sequences with nucleotide Blastand BlastX programs.◎ Results & Discussion : According to 16s rRNA sequencing results, we identified33 different nucleotide sequences of partial or coding including beta-glucanase ofseven, beta-glucosidase of twenty, xylanase of five and agarase of one. Almostgenes were novel sequences with 40~90% homologues. We are going to study forfinding full-length genes, and develop effective over-expression and purificationsystem for adjust of bioethanol production.