fa Biology & physiology Biology & physiology پژوهشي Orginal research papers <p>The intestinal bacterial diversity of <em>Stichopus japonicus</em> was investigated using 16S ribosomal RNA gene (rDNA) clone library and Polymerase Chain Reaction/Denaturing Gradient Gel Electrophoresis (PCR-DGGE). The clone library yielded a total of 188 clones, and these were sequenced and classified into 106 operational taxonomic units (OTUs) with sequence similarity ranging from 88 to 100%. The coverage of the library was 77.4%, with approximately 88.7% of the sequences affiliated to <em>Proteobacteria.</em><em> Gammaproteobacteria</em> and <em>Vibrio</em> sp. were the predominant groups in the intestine of <em>S. japonicus</em>. Some bacteria such as <em>Legionella </em>sp.<em>, Brachybacterium </em>sp.<em>, Streptomyces </em>sp.<em>, Propionigenium </em>sp. and <em>Psychrobacter</em> sp were first identified in the intestine of sea cucumber</p> Intestinal bacterial diversity, 16S rDNA, PCR-DGGE, Sequencing, Stichopus japonicus 318 325 http://jifro.ir/browse.php?a_code=A-10-600-68&slc_lang=fa&sid=1 M.L. Gao 100319475328460019665 100319475328460019665 No H.M. Hou houhongman2011@hotmail.com 100319475328460019666 100319475328460019666 Yes G.L. Zhang 100319475328460019667 100319475328460019667 No Y. Liu 100319475328460019668 100319475328460019668 No L.M. Sun 100319475328460019669 100319475328460019669 No