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Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Spatial and temporal dynamics of cellulose degradation and biofilm formation by Caldicellulosiruptor obsidiansis and Clostridium thermocellum | Wang et al. AMB Express 2011 1 30 http www.amb-express.eom content 1 1 30 o AMB Express a SpringerOpen Journal ORIGINAL Open Access Spatial and temporal dynamics of cellulose degradation and biofilm formation by Caldicellulosiruptor obsidiansis and Clostridium thermocellum Zhi-Wu Wang 1 Seung-Hwan Lee2 James G Elkins1 and Jennifer L Morrell-Falvey1 Abstract Cellulose degradation is one of the major bottlenecks of a consolidated bioprocess that employs cellulolytic bacterial cells as catalysts to produce biofuels from cellulosic biomass. In this study we investigated the spatial and temporal dynamics of cellulose degradation by Caldicellulosiruptfor obsidiansis which does not produce cellulosomes and Clostridium thermocellum which does produce cellulosomes. Results showed that the degradation of either regenerated or natural cellulose was synchronized with biofilm formation a process characterized by the formation and fusion of numerous crater-like depressions on the cellulose surface. In addition the dynamics of biofilm formation were similar in both bacteria regardless of cellulosome production. Only the areas of cellulose surface colonized by microbes were significantly degraded highlighting the essential role of the cellulolytic biofilm in cellulose utilization. After initial attachment the microbial biofilm structure remained thin uniform and dense throughout the experiment. A cellular automaton model constructed under the assumption that the attached cells divide and produce daughter cells that contribute to the hydrolysis of the adjacent cellulose can largely simulate the observed process of biofilm formation and cellulose degradation. This study presents a model based on direct observation correlating cellulolytic biofilm formation with cellulose degradation. Keywords biofilm thermophile cellulosome cellulose Introduction Biofuels provide a number of environmental advantages over fossil fuels especially in greenhouse gas reduction Hromadko et al. 2010 . .
