Genomic Analysis of Anabaena variabilis Mutants PK17 and PK84 That Are Characterised by High Production of Molecular Hydrogen

Sergey V. Shestakov, Lidia E. Mikheeva, Andrey V. Mardanov, Nikolai V. Ravin, Konstantin G. Skryabin
2013 Advances in microbiology  
The use of cyanobacteria for producing molecular hydrogen is one of the desirable tasks of photobiotechnology. Some years ago, we isolated several chemically induced mutants of the cyanobacterium Anabaena variabilis ATCC 29413 that exhibited a high level of H 2 -production; but the genetic nature of these mutants remained unresolved. To reveal mutations that could be responsible for enhancement of H 2 -production in two independent mutants, PK17 and PK84, the pyrosequencing of their entire
more » ... es was performed. The results were analyzed on the basis of comparison with the complete genome sequence of the reference strain Anabaena variabilis ATCC 29413. The genomes of mutants PK17 and RK84 contain 107 and 104 point deviations from the reference genome, respectively. The most probable reason for the increase of H 2 -production in mutant PK17 is the mutation identified in the gene hupL encoding the large subunit of uptake hydrogenase. A high level of H 2 -production in mutant PK84 could be the result of a mutation in a conserved part of the gene hypF, which participates in the post-translation maturation of hydrogenase complexes. Figure S1. Alignment of the amino acid sequences of the C-terminal regions of various HupL proteins. Amino acids highlighted in grey are analogues of Cys 446 of HupL of A. variabilis. Residues that are identical (*), conserved (:), or semiconserved (.) in the sequences are indicated below the sequences. Conserved aminoacids of the active sites are shown bold and underlined. The C-end segment that is cleaved by the HupW-endopeptidase is shown in bold italics. (Abbreviations after enzyme sequences are shown in the Table S5 ).
doi:10.4236/aim.2013.34049 fatcat:kly7ev7no5bphdl3jrdc74rare