Nostoc sp. strain PCC 73102 and H-2: Knowledge, research, and biotechnological challenges

• Type: Article in International Conference Proceedings Book
• Date: 1998

Authors

Lindblad, P (Author) Other; Hansel, A (Author) Other; Oxelfelt, F (Author) Other; Tamagnini, P (Author) FCUP

Conference proceedings International

Title: HYDROGEN ENERGY PROGRESS XII, VOLS 1-3

Pages: 2035-2044

12th World Hydrogen Energy Conference

BUENOS AIRES, ARGENTINA, JUN 21-26, 1998

Indexing

ISI Web of Knowledge - 0 Citations

Scientific classification

FOS: Engineering and technology > Environmental engineering

Other information

Authenticus ID: P-00G-94J

Abstract (EN): In N-2-fixing cyanobacteria at least three enzymes may be involved in H-2 metabolism; (a) nitrogenase, evolving H-2 during N-2 fixation, (b) an uptake hydrogenase, reutilizing this H-2, and, (c) a bidirectional (reversible) hydrogenase. Our studies focus on the hydrogen metabolism of the filamentous, heterocystous cyanobacterium Nostoc sp. strain PCC 73102, a free-living strain originally isolated from coralloid roots of the Australian cycad Macrozamia. Immunological studies using polyclonal antisera directed against hydrogenases purified from several different microorganisms ir dicated the presence of two native enzymes/forms in N-2-fixing cells of Nostoc sp. strain PCC 73102, with at lease one common subunit of approximately 58 kD. Moreover, a cellular localization in both the N-2-fixing heterocysts and the vegetative cells was observed. Measurements with an H-2-electrode revealed the presence of a light-stimulated in vivo H-2-uptake in N-2-fixing cells of Nostoc sp. strain PCC 73102. We have identified and sequenced genes encoding an uptake hydrogenase (hupSL) in Nostoc sp. strain PCC 73102. They are highly homologous to corresponding genes in Anabaena sp. strain PCC 7120. However, there is no rearrangement within hupL. Using both molecular and physiological techniques, it was not possible to demonstrate any evidence for the presence of either hox genes or corresponding bidirectional enzyme activities in Nostoc sp. strain PCC 73102. This fact, together with the availability of the genes encoding an uptake hydrogenase, makes Nostoc sp. strain sp. strain PCC 73102 an interesting candidate for further molecular studies of its hydrogen metabolism.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10