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Overexpression of the groESL operon enhances the heat and salinity stress tolerance of the nitrogen-fixing cyanobacterium Anabaena sp. strain PCC7120.

ABSTRACT: The bicistronic groESL operon, encoding the Hsp60 and Hsp10 chaperonins, was cloned into an integrative expression vector, pFPN, and incorporated at an innocuous site in the Anabaena sp. strain PCC7120 genome. In the recombinant Anabaena strain, the additional groESL operon was expressed from a strong cyanobacterial P(psbA1) promoter without hampering the stress-responsive expression of the native groESL operon. The net expression of the two groESL operons promoted better growth, supported the vital activities of nitrogen fixation and photosynthesis at ambient conditions, and enhanced the tolerance of the recombinant Anabaena strain to heat and salinity stresses.

SUBMITTER: Chaurasia AK

PROVIDER: S-EPMC2747873 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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Overexpression of the groESL operon enhances the heat and salinity stress tolerance of the nitrogen-fixing cyanobacterium Anabaena sp. strain PCC7120.

Chaurasia Akhilesh Kumar AK Apte Shree Kumar SK

Applied and environmental microbiology 20090724 18

The bicistronic groESL operon, encoding the Hsp60 and Hsp10 chaperonins, was cloned into an integrative expression vector, pFPN, and incorporated at an innocuous site in the Anabaena sp. strain PCC7120 genome. In the recombinant Anabaena strain, the additional groESL operon was expressed from a strong cyanobacterial P(psbA1) promoter without hampering the stress-responsive expression of the native groESL operon. The net expression of the two groESL operons promoted better growth, supported the v ...[more]

PMID: 19633117

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Anabaena PCC7120 infection with Cyanophage A1

Project description:In order to examine the response of Anabaena sp. PCC 7120 to an infection of the Cyanophage A1, we have used customized microarrays to identify genes potentially up- or downregulated by the infection. For this we compared cell culture before and after infection.

2023-11-01 | GSE183630 | GEO

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