SREL Reprint #3027

Clostridium acidtolerans sp. nov., an acid-tolerant spore-forming anaerobic bacterium from contructed wetland sediment

Yong-Jin Lee,1,3 Christopher S. Romanek,2,3 and Juergen Wiegel1

1Department of Microbiology, University of Georgia, Athens, GA 30602, USA
2Department of Geology, University of Georgia, Athens, GA 30602, USA
3Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA

Abstract: An obligately anaerobic, spore-forming, moderately acid-tolerant bacterium, strain JW/YJL-B3T, was isolated from a sediment sample from a constructed wetland system receiving acid sulfate water. Based on 16S rRNA gene sequence analysis, the isolate belonged to the Firmicutes branch with Clostridium drakei SL1T (96.2% gene sequence similarity) as its closest relative. The G+C content of the genomic DNA was 30.8 mol% (HPLC). Cells were straight to curved rods, 0.5-1.0 µm in diameter and 3.0-9.0 µm in length. The temperature range for growth was 20-45°C, with an optimum around 35°C. Growth was not detected below 18°C or above 47°C. The pH range for growth was broad, pH25°C 3.8-8.9, with an optimum at 7.0-7.5. However at pH 4.5, the strain grew at 52% of the optimal growth rate. The salinity range was 0-1.5% NaCl (w/v). Strain JW/YJL-B3T utilized beef extract, Casamino acids, peptone, tryptone, arabinose, cellobiose, fructose, galactose, glucose, lactose, maltose, mannose, raffinose, ribose, sucrose, xylose, pyruvate, glutamate and inulin as a carbon and energy source. There were no indications of growth under aerobic or autotrophic conditions. The isolate produced acetate, butyrate and ethanol as fermentation end products from glucose. Based on these characteristics and other physiological properties, the isolate is placed into the novel taxon, Clostridium acidtolerans sp. nov., with strain JW/YJL-B3T (=DSM 17425T=ATCC BAA-1220T) as the type strain.

SREL Reprint #3027

Lee, Y., C. S. Romanek, and J. Wiegel. 2007. Clostridium acidtolerans sp. nov., an acid-tolerant spore-forming anaerobic bacterium from contructed wetland sediment. International Journal of Systematic and Evolutionary Microbiology 57:311-315.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).