变性梯度凝胶电泳分析草菇培养料二次发酵过程中细菌群落演替

Denaturing gradient gel electrophoresis analysis on bacterial community change in the phase Ⅱ composting of Volvariella volvacea substrate

摘要:

摘要:【目的】了解草菇以废棉为主要成分的培养料在二次发酵过程中细菌群落结构变化情况，确定发酵不同阶段的优势菌群，为能够在分子水平上快速准确地监测发酵过程中菌群动态变化奠定基础。【方法】采用变性梯度凝胶电泳(denaturing gradient gel electrophoresis，DGGE)及克隆菌株16S rDNA 序列分析技术对草菇废棉培养料二次发酵不同阶段的样品中细菌群落结构进行分析。【结果】DGGE 图谱显示，细菌群落多样性较为丰富，条带多样性随着发酵进程逐渐降低，而且在不同阶段中的优势条带及相对丰度在发生着动态的变化。回收克隆的23个不同发酵阶段的优势菌株来自于变形菌门、拟杆菌门和厚壁菌门，α，β，γ-变形菌纲、鞘脂杆纲、拟杆菌纲和梭菌纲6 个菌纲的11 个属，其中19 株克隆菌株为耐热细菌，在发酵的高温及降温阶段，丛毛单胞菌属、鞘脂杆菌属、中华根瘤菌属和寡养单胞菌属细菌为优势类群。【结论】草菇废棉培养料二 次发酵过程中细菌的群落结构及优势菌群在发生着动态的变化，尤其是在进入高温期阶段，优势菌群变化显著。

Abstract:

Abstract:［Objective］To study the bacterial community change during the phase II composting of Volvariella volvacea substrate of cotton waste and to clarify the predominant bacteria at different composting stages． Methods］ The 16S rDNA-DGGE (denaturing gradient gel electrophoresis) and clone strains sequencing methods were used to track the change of bacterial community during composting．［Results］ The DGGE profile shows that the diversity of bacterial community was rich and bands diversity decreased with the composting progress． The dynamic changes of predominant community and relative intensity were observed． The 23 predominant strains belong to 3 classes of Proteobacteria，Bacteroidetes and Firmicutes，6 families of α，β，γ-Proteobacterium，Bacteroidetes，Sphingobacteria and Clostridia，11 genera，in which 19 strains were thermophilic bacteria． The genera of Stenotrophomonas，Comamonas，Sphingobacterium and Sinorhizobium were predominant bacteria in the stages of high temperature and drop of temperature during composting．［Conclusion］The bacterial community structure and predominant community change dynamically during the phase II of Volvariella volvacea composting，especially in the course of entering the stage of high temperature．