GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:22383473

From GONUTS
Jump to: navigation, search
Citation

Ehira, S and Ohmori, M (2012) The pknH gene restrictively expressed in heterocysts is required for diazotrophic growth in the cyanobacterium Anabaena sp. strain PCC 7120. Microbiology (Reading, Engl.) 158:1437-43

Abstract

Anabaena sp. strain PCC 7120 is a filamentous cyanobacterium in which certain vegetative cells differentiate into heterocysts, which are specialized cells for nitrogen fixation. Heterocysts are unable to carry out photosynthesis and are supplied with carbohydrate required for nitrogen fixation from neighbouring vegetative cells. Thus, filament integrity is very important for diazotrophic growth of the heterocystous cyanobacteria. The pknH gene (alr1336), encoding a putative Ser/Thr protein kinase, was upregulated in heterocysts after nitrogen deprivation. Its expression was developmentally regulated by the hetR gene. Expression levels of genes involved in heterocyst maturation, such as hepA, hglE and nifH, in the pknH disruptant were similar to those of the wild-type strain. The disruptant was able to form heterocysts with nitrogenase activity, but most heterocysts were detached from filaments. Hence, the pknH disruptant showed a growth defect in the medium without combined nitrogen. It is concluded that the pknH gene is not involved in the development of heterocyst function but is involved in maintaining connections between heterocysts and vegetative cells.

Links

PubMed Online version:10.1099/mic.0.057729-0

Keywords

Anabaena/enzymology; Anabaena/genetics; Anabaena/growth & development; Bacterial Proteins/genetics; Bacterial Proteins/metabolism; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Developmental; Gene Expression Regulation, Enzymologic; Protein-Serine-Threonine Kinases/genetics; Protein-Serine-Threonine Kinases/metabolism

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

MYCTU:PKNH

GO:0045927: positive regulation of growth

ECO:0000314:

P

Figure 4b. pknH is required for diazotrophic growth

complete
CACAO 9150

See also

References

See Help:References for how to manage references in GONUTS.