Screening and Biodiversity Analysis of Agarolytic Bacteria in the Qingdao Coast

A preliminary screening for agar-degrading bacteria from the coastal waters of Qingdao yielded 87 isolates with promising agarolytic activity,among which 15 strains were selected for further analysis.To investigate the phylogenetic position of these strains,the 16S rDNA sequences were cloned,sequenced and compared with those of related strains.A molecular phylogenetic dendrogram was constructed based on genetic distance analysis.The strains were classified as members of genera Cellulophaga,Cytophaga,Microbulbifer,Glaciecola,Pseudoalteromonas,Pseudomonas,Alteromonas and Agarivorans.Strains QM5,QM21 and QM36 were identified to be Cellulophaga lytica.Strains QM15 and QM28 were identified to be Glaciecola mesophila.Strains QM11,QM35,QM47 and QM65 were identified to be Cytophaga fucicola,Pseudoalteromonas atlantica,Pseudoalteromonas haloplanktis and Alteromonas addita,respectively.