RESUMO
The cellulolytic bacterial community structure in gastrointestinal (GI) tract of Achatina fulica was studied using culture-independent and -dependent methods by enrichment in carboxymethyl cellulose (CMC). Culture-dependent method indicated that GI tract of snail was dominated by Enterobacteriaceae members. When tested for cellulase activities, all isolates obtained by culture-dependent method showed both or either of CMCase or avicelase activity. Isolate identified as Citrobacter freundii showed highest CMCase and medium avicelase activity. Sequencing of clones from the 16S rRNA gene clone library identified ten operational taxonomic units (OTUs), which were affiliated to Enterobacteriaceae of phylum Gammaproteobacteria. Of these ten OTUs, eight OTUs closely matched with Enterobacter and Klebsiella genera. The most abundant OTU allied to Klebsiella oxytoca accounted for 70 % of the total sequences. The members of Klebsiella and Enterobacter were observed by both methods indicating their dominance among the cellulolytic bacterial community in the GI tract of the snail.
Assuntos
Proteínas de Bactérias/metabolismo , Celulases/metabolismo , Citrobacter/isolamento & purificação , Enterobacter/isolamento & purificação , Trato Gastrointestinal/microbiologia , Klebsiella/isolamento & purificação , Caramujos/microbiologia , Animais , Proteínas de Bactérias/genética , Carboximetilcelulose Sódica/metabolismo , Celulases/genética , Citrobacter/classificação , Citrobacter/enzimologia , Citrobacter/genética , Enterobacter/classificação , Enterobacter/enzimologia , Enterobacter/genética , Expressão Gênica , Biblioteca Gênica , Klebsiella/classificação , Klebsiella/enzimologia , Klebsiella/genética , Microbiota/genética , Filogenia , RNA Ribossômico 16S/genética , SimbioseRESUMO
"Chirayat" represents a group in which different species of Swertia and some other non-Swertia species are used as local substitutes/adulterants for the Swertia chirayita. Twelve different taxa recognized under "Chirayat" complex were characterized using ISSR markers. On the basis of preliminary screening, 16 informative primers were selected for molecular profiling. All the ISSR primers generated distinct DNA amplification profiles, which could be used for identification of an individual taxon in the group. Primers with anchors at 5' end generated the most polymorphic profiles. Based on their ability to distinguish between the taxa, expressed as resolving power (Rp), primer 885 showed the highest resolving power and 855 the least. A total of 332 reproducible bands were scored and all of them were polymorphic. In the cluster analysis of Swertia SPP., based on the band data, two main clusters were observed. The first consisted of S. angustifolia and S. cordata; and the other of the remaining species of Swertia. Based on the similarity coefficient, S. lurida was closest to S. chirata. The utility of ISSR markers for the authentication of commercial crude drug samples is also demonstrated. The results show that ISSR is an efficient and reliable marker system for the molecular authentication of medicinal plants as well as commercial crude drug samples.
