Article

Halanaerobacter jeridensis sp nov., isolated from a hypersaline lake

Laboratoire des Bio-Procédés Environnementaux, Centre de Biotechnologie de Sfax, BP 1177, 3018 Sfax, Tunisia.
International Journal of Systematic and Evolutionary Microbiology (Impact Factor: 2.51). 10/2011; 62(Pt 8):1970-3. DOI: 10.1099/ijs.0.036301-0
Source: PubMed

ABSTRACT

An obligatory anaerobic, moderately halophilic bacterium, designated strain CEJFG43(T), was isolated from a sample of sediment collected below the salt crust on the hypersaline El Jerid lake, in southern Tunisia. The cells of this novel strain were Gram-staining-negative, non-sporulating, motile, short rods. They grew in media with 6-30% (w/v) NaCl (optimum 15%), at 20-60 °C (optimum 45 °C) and at pH 5.5-9.5 (optimum pH 8.3). The micro-organism fermented glucose, fructose, ribose, raffinose, galactose, mannose, sucrose, maltose, xylose, mannitol, pyruvate and glycerol. The products of glucose fermentation were lactate, ethanol, acetate, H(2) and CO(2). The genomic G+C DNA content of strain CEJFG43(T) was 33.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CEJFG43(T) belonged in the genus Halanaerobacter and was most closely related to Halanaerobacter lacunarum DSM 6640(T) (95.3% gene sequence similarity) and Halanaerobacter chitinivorans DSM 9569(T) (95.3%). The predominant cellular fatty acids were non-branched (C(16:0) and C(16:1)). Based on the phylogenetic and phenotypic evidence, strain CEJFG43(T) represents a novel species in the genus Halanaerobacter for which the name Halanaerobacter jeridensis sp. nov. is proposed. The type strain is CEJFG43(T) ( = DSM 23230(T) = JCM 16696(T)).

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Available from: Fatma Karray, Nov 18, 2015
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    • "This is the first report describing the microbial populations present in the water and sediment of Chott El Jerid using molecular methods [denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR]. Few ecological studies of this environment based on the cultivation approach have been investigated (Ben Abdallah et al. 2015; Mezghani et al. 2012). The main purpose of this research is to obtain an overview of the abundance, the structure, and microbial diversity of both archaeal and bacterial communities in water and sediment samples of Chott El Jerid using culture-dependent and culture-independent techniques. "
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