Open AccessImmunolocalization of the uptake hydrogenase in the marine cyanobacterium Lyngbya majuscula CCAP 1446/4 and two Nostoc strains
Author(s) -
Seabra Rui,
Santos Arlete,
Pereira Sara,
MoradasFerreira Pedro,
Tamagnini Paula
Publication year - 2009
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2008.01471.x
Subject(s) - hydrogenase , cyanobacteria , heterocyst , thylakoid , biology , biochemistry , nostoc , enzyme , trichodesmium , diazotroph , microbiology and biotechnology , bacteria , chloroplast , nitrogen fixation , gene , anabaena , genetics
In N 2 ‐fixing cyanobacteria, the reduction of N 2 to NH 3 is coupled with the production of molecular hydrogen, which is rapidly consumed by an uptake hydrogenase, an enzyme that is present in almost all diazotrophic cyanobacteria. The cellular and subcellular localization of the cyanobacterial uptake hydrogenase remains uncertain, and it is definitely strain dependent. Previous studies focused mainly on heterocystous cyanobacteria and used heterologous antisera. The present work represents the first effort to establish the subcellular localization of the uptake hydrogenase in a N 2 ‐fixing filamentous nonheterocystous cyanobacterium, Lyngbya majuscula CCAP 1446/4, using the first antiserum produced against a cyanobacterial uptake hydrogenase. The data obtained revealed higher specific labelling associated with the thylakoid membranes of L. majuscula , reinforcing the idea that the cyanobacterial uptake hydrogenase is indeed a membrane‐bound protein. For comparative purposes, the localization of the uptake hydrogenase was also investigated in two distinct heterocystous cyanobacterial strains, and while in Nostoc sp. PCC 7120 the labelling was only observed in the heterocysts, in Nostoc punctiforme , the presence of uptake hydrogenase antigens was detected in both the vegetative cells and heterocysts, corresponding most probably to an inactive and an active form of the enzyme.