Molecular cloning and characterization of hetR genes from filamentous cyanobacteria |
| |
Authors: | Schiefer Wolfgang Schütz Kathrin Hachtel Wolfgang Happe Thomas |
| |
Institution: | Botanisches Institut, Universit?t Bonn, Karlrobert-Kreiten-Strasse 13, 53115 Bonn, Germany. |
| |
Abstract: | HetR, a serine type protease, plays an important role in heterocyst differentiation in filamentous cyanobacteria. We isolated and sequenced the hetR genes from different heterocystous and filamentous nonheterocystous cyanobacteria. The hetR gene in the heterocyst forming Anabaena variabilis ATCC 29413 FD was interrupted by interposon mutagenesis (mutant strain WSIII8). This mutant does not form heterocysts and shows no diazotrophic growth under aerobic conditions. However, under anaerobic N(2)-fixing conditions, the WSIII8 cells are able to grow, and high nitrogenase (Nif2) activity is detectable. Nif2 expression was demonstrated in each vegetative cell of the filament by immunolocalization 4 h after nitrogen step-down. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|