CO2 Production as an Indicator of Biofilm Metabolism
CO2 Production as an Indicator of Biofilm Metabolism
复制标题
DOI：
10.1128/aem.01567-08
复制
发表时间：
2009-07-01
影响因子：
4.4
通讯作者：
Wolfaardt, Gideon M.
中科院分区：
文献类型：
--
作者：
Kroukamp, Otini;Wolfaardt, Gideon M.
生物膜在水体营养物质循环和微生物增殖中具有重要作用。在这些结构中，碳等营养物质被引导到细胞外聚合物或细胞分裂的生产中;两者对微生物的生存和繁殖都至关重要。本研究的目的是评估碳通道进入细胞或非细胞部分的生物膜。在管式反应器中生长，我们的模型菌株假单胞菌属菌株CT 07的生物膜从生物膜发育的早期阶段产生细胞到增殖期，达到假稳态，具有类似于10（7）个细胞的一致产量。cm（-2）。h（-1）。总直接计数和图像分析表明，大部分转化碳发生在非细胞部分，释放的细胞和固着细胞分别占流入碳的< 10%和< 2%。开发了一种监测气相中CO2的CO2释放测量系统（CEMS），以在整个生物膜上进行完整的碳平衡。该测量系统能够在真实的时间内确定整个生物膜的CO2生产率，并显示气态CO2生产占流入碳的25%。此外，CEMS使测量生物膜对变化的环境条件的响应成为可能;温度或流入碳浓度的变化之后是生物膜代谢的快速响应和新的稳态条件的建立。
Biofilms are important in aquatic nutrient cycling and microbial proliferation. In these structures, nutrients like carbon are channeled into the production of extracellular polymeric substances or cell division; both are vital for microbial survival and propagation. The aim of this study was to assess carbon channeling into cellular or noncellular fractions in biofilms. Growing in tubular reactors, biofilms of our model strain Pseudomonas sp. strain CT07 produced cells to the planktonic phase from the early stages of biofilm development, reaching pseudo steady state with a consistent yield of similar to 10(7) cells . cm(-2) . h(-1) within 72 h. Total direct counts and image analysis showed that most of the converted carbon occurred in the noncellular fraction, with the released and sessile cells accounting for < 10% and < 2% of inflowing carbon, respectively. A CO2 evolution measurement system (CEMS) that monitored CO2 in the gas phase was developed to perform a complete carbon balance across the biofilm. The measurement system was able to determine whole-biofilm CO2 production rates in real time and showed that gaseous CO2 production accounted for 25% of inflowing carbon. In addition, the CEMS made it possible to measure biofilm response to changing environmental conditions; changes in temperature or inflowing carbon concentration were followed by a rapid response in biofilm metabolism and the establishment of new steady-state conditions.