Analysis of cellulolytic and hemicellulolytic enzyme activity within the Tipula abdominalis （Diptera： Tipulidae） larval gut and characterization of Crocebacterium ilecola gen. nov., sp. nov., isolated from the Tipula abdominalis larval hindgut  

作　　者：Theresa E. Rogers Joy Doran-Peterson 

机构地区：[1]Microbiology Department, University of Georgia, Athens, Georgia, USA

出　　处：《Insect Science》2010年第3期291-302,共12页昆虫科学（英文版）

摘　　要：In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and diverse microbial community in their hindgut that may aide in the degradation oflignocellulose. In this study, the activities ofcellulolytic and hemicellulolytic enzymes were demonstrated from hindgut extracts and from bacterial isolates using model sugar substrates. One of the bacterial isolates was further characterized as a member of the family Microbacteriaceae. Taxonomic position of the isolate within this family was determined by a polyphasic approach, as is commonly employed for the separation of genera within the family Microbacteriaceae. The bacterial isolate is Gramtype positive, motile, non-sporulating, and rod-shaped. The G ＋ C content of the DNA is 64.9 mol%. The cell wall contains B2y type peptidoglycan, D- and L-diaminobutyric acid as the diamino acid, and rhamnose as the predominant sugar. The predominant fatty acids are 12-methyltetradecanoic acid （ai-C15：0） and 14-methylhexadecanoic acid （ai-C17：0）. The isolate forms a distinct lineage within the family Microbacteriaceae, as determined by 16S rRNA sequence analysis. We propose the name Crocebacterium ilecola gen. nov., sp. nov., to accommodate this bacterial isolate. The type species is T202T （ATCC BAA-1359; GenBank Accession DQ826511）.In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and diverse microbial community in their hindgut that may aide in the degradation oflignocellulose. In this study, the activities ofcellulolytic and hemicellulolytic enzymes were demonstrated from hindgut extracts and from bacterial isolates using model sugar substrates. One of the bacterial isolates was further characterized as a member of the family Microbacteriaceae. Taxonomic position of the isolate within this family was determined by a polyphasic approach, as is commonly employed for the separation of genera within the family Microbacteriaceae. The bacterial isolate is Gramtype positive, motile, non-sporulating, and rod-shaped. The G ＋ C content of the DNA is 64.9 mol%. The cell wall contains B2y type peptidoglycan, D- and L-diaminobutyric acid as the diamino acid, and rhamnose as the predominant sugar. The predominant fatty acids are 12-methyltetradecanoic acid （ai-C15：0） and 14-methylhexadecanoic acid （ai-C17：0）. The isolate forms a distinct lineage within the family Microbacteriaceae, as determined by 16S rRNA sequence analysis. We propose the name Crocebacterium ilecola gen. nov., sp. nov., to accommodate this bacterial isolate. The type species is T202T （ATCC BAA-1359; GenBank Accession DQ826511）.

关 键 词：CELLULOLYTIC hemicellulolytic HINDGUT 

分 类 号：Q969.453.8[生物学—昆虫学] X773[环境科学与工程—环境工程]