Cloning and Characterization of hoxH Genes from Arthrospira and Spirulina and Application in Phylogenetic Study

Institute of Biological Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
Marine Biotechnology (Impact Factor: 3.27). 08/2005; 7(4):287-96. DOI: 10.1007/s10126-004-3127-9
Source: PubMed


Partial hoxH genes of 2 cyanobacterial genera, including 5 strains of Arthrospira and 2 strains of Spirulina, were cloned and characterized. This gene encodes the large subunit of nickel-iron hydrogenase. The results showed that these genes comprised 1349 nucleotides in Arthrospira and 1343 nucleotides in Spirulina, respectively. The GC contents of hoxH were 45.7% to 47.3% in Arthrospira and up to 50.4% to 50.9% in Spirulina. The hoxH gene was demonstrated to be single copy by Southern analysis, and its transcription was verified by reverse transcriptase polymerase chain reaction in Arthrospira platensis FACHB341. The similarities of nucleotide sequences among the 5 strains of Arthrospira ranged from 95.7% to 99.8%, which are higher than those between Arthrospira and Spirulina (72.9-77.0%). However, similarity between the 2 Spirulina strains was only 72.5%, slightly lower than that between the 2 genera. A phylogenetic tree based on hoxH was constructed. All 5 strains of Arthrospira formed a monophyletic clade, which was highly supported by bootstrap value, while the 2 strains of Spirulina were separated into 2 different clades.

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Available from: Yunxiang Mao, Oct 01, 2014
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    • "Herein we show that addition of adequate nickel concentration to the growth medium plays a dominant role in the capacity for H 2 production by the filamentous nondiazotrophic cyanobacterium Arthrospira maxima. This organism possesses a bidirectional NiFe-hydrogenase (hox gene cluster) [18] that produces H 2 in the dark, but apparently no nitrogenase (nif gene cluster) nor any uptake class of hydrogenase (hup gene cluster) (unpublished data). As a result of this simplicity, A. maxima is a good candidate for mechanistic studies of H 2 metabolism by the bidirectional NiFe-hydrogenase. A. maxima is a filamentous nonheterocystous nondiazotrophic cyanobacterium isolated from alkaline soda lakes in East Africa. "
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