title: Functional analysis of long-chain n-alkane degradation by Dietzia spp.
abstract: The genetic background of long-chain n-alkane degradation was investigated in detail in strain E1, a member of the genetically unexplored Dietzia genus. A suicide vector carrying a 518-bp alkB fragment was site-specifically integrated into the E1 chromosome, and the full alkB, as well as its chromosomal environment was sequenced after plasmid rescue experiments. Four out of the nine putative genes were strongly induced by long-chain n-alkanes in wild-type E1. ORF4 encoded a natural fusion protein consisting of an integral membrane alkane hydroxylase and a rubredoxin domain. The significance of the alkB-rub gene in n-alkane degradation was investigated in phenotypic tests, and the disruption mutant strain exhibited severely impaired growth on n-C(20) alkane carbon source. The mutation was successfully complemented with the expression of intact AlkB-Rub protein, the full-length form of which was detected by simultaneous immunoblotting. The presented data furnish the first experimental evidence of the in vivo existence of an AlkB-Rub natural fusion protein, which plays a major role in long-chain n-alkane degradation.
authors.affiliation: Institute for Biotechnology, Bay Zoltán Foundation for Applied Research, Szeged, Hungary. bihari@bay.u-szeged.hu
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Bihari
authors.forename: Attila
authors.initials: A
authors.lastname: Szvetnik
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Szabó
authors.forename: András
authors.initials: A
authors.lastname: Blastyák
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Zombori
authors.forename: Margit
authors.initials: M
authors.lastname: Balázs
authors.forename: István
authors.initials: I
authors.lastname: Kiss
mesh_terms: D000192:Actinomycetales / Q000737:chemistry / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D000473:Alkanes / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D042926:Cytochrome P-450 CYP4A / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D016415:Sequence Alignment
chemical_list: D000473:Alkanes; D001426:Bacterial Proteins; D042926:Cytochrome P-450 CYP4A