title: Clostridium tunisiense sp. nov., a new proteolytic, sulfur-reducing bacterium isolated from an olive mill wastewater contaminated by phosphogypse.
abstract: A new sporulated fermentative bacterium designated strain E1(T) (T=type strain), was isolated from an anaerobic mud of an olive mill wastewater basin contaminated by phosphogypse produced by a Tunisian factory. Strain E1(T) was a motile Gram-positive slightly curved rod with spherical terminal spore swelling the cell. It grew between 18 degrees C and 43 degrees C with an optimum at 37 degrees C and pH 7.8 (range 5.5-8.7), without NaCl (range 0-3%). Strain E1(T) was a chemoorganotrophic anaerobic bacterium fermenting only proteins and amino acids. Yeast extract was required for growth. Elemental sulfur was used as terminal electron acceptor. The G+C content of the DNA was 32.6 mol%. The closest phylogenetical relatives of strain E1(T) were Clostridium thiosulfatireducens and C. subterminale (97.3% similarity for partial rRNA gene sequences). DNA-DNA hybridization values between strain E1(T) and both species were 17% and 20.8%, respectively. On the basis of differences in genotypic and phenotypic characteristics, strain E1(T) (DSM 15206(T), CIP 107666(T)) is proposed as the type strain of a new species, C. tunisiense sp. nov. GenBank accession number for the 16S rRNA gene sequence of strain E1(T) is AY187622.
authors.affiliation: Laboratoire de Microbiologie IRD, UR 101 Extrêmophiles, IFR-BAIM, Universités de Provence et de la Méditerranée, ESIL case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 9, France.
authors.forename: Olfa Ben Dhia
authors.initials: OB
authors.lastname: Thabet
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Fardeau
authors.forename: Catherine
authors.initials: C
authors.lastname: Joulian
authors.forename: Pierre
authors.initials: P
authors.lastname: Thomas
authors.forename: Moktar
authors.initials: M
authors.lastname: Hamdi
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Garcia
authors.forename: Bernard
authors.initials: B
authors.lastname: Ollivier