Cellular and functional specificity among ferritin-like proteins in the multicellular cyanobacterium Nostoc punctiforme

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Ekman, M (Author) Other; Sandh, G (Author) Other; Nenninger, A (Author) Other; Oliveira, P (Author) Other; Stensjo, K (Author) Other

Journal

Title: Environmental Microbiology

Vol. 16

Pages: 829-844

ISSN: 1462-2912

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 27 Citations

Other information

Authenticus ID: P-009-6WJ

DOI: 10.1111/1462-2920.12233

Abstract (EN): Ferritin-like proteins constitute a remarkably heterogeneous protein family, including ferritins, bacterioferritins and Dps proteins. The genome of the filamentous heterocyst-forming cyanobacterium Nostoc punctiforme encodes five ferritin-like proteins. In the present paper, we report a multidimensional characterization of these proteins. Our phylogenetic and bioinformatics analyses suggest both structural and physiological differences among the ferritin-like proteins. The expression of these five genes responded differently to hydrogen peroxide treatment, with a significantly higher rise in transcript level for Npun_F3730 as compared with the other four genes. A specific role for Npun_F3730 in the cells tolerance against hydrogen peroxide was also supported by the inactivation of Npun_F3730, Npun_R5701 and Npun_R6212; among these, only the Npun_F3730 strain showed an increased sensitivity to hydrogen peroxide compared with wild type. Analysis of promoter-GFP reporter fusions of the ferritin-like genes indicated that Npun_F3730 and Npun_R5701 were expressed in all cell types of a diazotrophic culture, while Npun_F6212 was expressed specifically in heterocysts. Our study provides the first comprehensive analysis combining functional differentiation and cellular specificity within this important group of proteins in a multicellular cyanobacterium.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 16