title: Gracilibacter thermotolerans gen. nov., sp. nov., an anaerobic, thermotolerant bacterium from a constructed wetland receiving acid sulfate water.
abstract: An obligatorily anaerobic, thermotolerant, asporogenic bacterium, strain JW/YJL-S1(T), was isolated from a sediment sample of a constructed wetland system receiving acid sulfate water (pH 1.6-3.0). Cells of strain JW/YJL-S1(T) were straight to curved rods 0.2-0.4 mum in diameter and 2.0-7.0 mum in length, and stained Gram-negative. Growth of strain JW/YJL-S1(T) was observed at 25-54 degrees C (no growth at or below 20 or at or above 58 degrees C), with an optimum temperature range for growth of 42.5-46.5 degrees C. The pH(25 degrees C) range for growth was 6.0-8.25 (no growth at or below pH 5.7 or at or above pH 8.5), with optimum growth at pH 6.8-7.75. The salinity range for growth was 0-1.5 % (w/v) NaCl, with an optimum at 0-0.5 %. During growth on glucose the isolate produced acetate, lactate and ethanol as main fermentation end products. The fatty acid composition was dominated by branched-chain compounds: i15 : 0, a15 : 0, i16 : 0 and i17 : 0. The G+C content of the genomic DNA was 42.8 mol% (HPLC). Strain JW/YJL-S1(T) showed polymorphism of the 16S rRNA gene. Its closest relative was the thermophilic Clostridium thermosuccinogenes DSM 5807(T) (a member of Clostridium cluster III) (a blastn search revealed Clostridium pascui DSM 10365(T) to have 92.7 % gene sequence similarity, the highest value). The inferred phylogenetic trees placed strain JW/YJL-S1(T) between Clostridium clusters I/II and III. Based on the morphological and phylogenetic data presented, JW/YJL-S1(T) (=DSM 17427(T)=ATCC BAA-1219(T)) is proposed as the type strain of a novel species in a new genus, Gracilibacter thermotolerans gen. nov., sp. nov.
authors.affiliation: Savannah River Ecology Laboratory, Aiken, SC 29802, USA.|Department of Microbiology, The University of Georgia, Athens, GA 30602, USA.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Department of Geology, The University of Georgia, Athens, GA 30602, USA.|Savannah River Ecology Laboratory, Aiken, SC 29802, USA.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Romanek
authors.affiliation: Savannah River Ecology Laboratory, Aiken, SC 29802, USA.
authors.forename: Gary L
authors.initials: GL
authors.lastname: Mills
authors.affiliation: Department of Cellular Biology, The University of Georgia, Athens, GA 30602, USA.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Davis
authors.affiliation: Department of Microbiology, The University of Georgia, Athens, GA 30602, USA.
authors.forename: William B
authors.initials: WB
authors.lastname: Whitman
authors.affiliation: Department of Microbiology, The University of Georgia, Athens, GA 30602, USA.
authors.forename: Juergen
authors.initials: J
authors.lastname: Wiegel
mesh_terms: D001421:Bacteria, Anaerobic / Q000145:classification / Q000378:metabolism; D003013:Clostridium / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics; D013431:Sulfates / Q000378:metabolism*; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D013431:Sulfates