| dc.creator |
El-Shehawy, Rehab |
|
| dc.creator |
Lugomela, Charles |
|
| dc.creator |
Ernst, A. |
|
| dc.creator |
Bergman, Birgitta |
|
| dc.date |
2016-06-19T21:28:58Z |
|
| dc.date |
2016-06-19T21:28:58Z |
|
| dc.date |
2003 |
|
| dc.identifier |
El-Shehawy, R., Lugomela, C., Ernst, A. and Bergman, B., 2003. Diurnal expression of hetR and diazocyte development in the filamentous non-heterocystous cyanobacterium Trichodesmium erythraeum. Microbiology, 149(5), pp.1139-1146. |
|
| dc.identifier |
http://hdl.handle.net/20.500.11810/2610 |
|
| dc.description |
The marine non-heterocystous cyanobacterium Trichodesmium fixes atmospheric N2 aerobically in
light. In situ immunolocalization/light microscopy of NifH revealed that lighter, non-granulated cell
regions observed correspond to the nitrogenase-containing diazocyte clusters in Trichodesmium
IMS101. The number of diazocyte clusters per trichome varied from 0 to 4 depending on trichome
length. The constant percentage of diazocytes (approx. 15 %) in cultured strains and five natural
populations suggests a developmentally regulated differentiation process. Real-time RT-PCR
showed that ntcA, encoding the global nitrogen regulator in cyanobacteria, and hetR, the key
regulatory gene in heterocyst differentiation, are both constitutively expressed during a 12 h/12 h
light/dark cycle. hetR in addition showed a distinct peak in the dark (close to midnight) while nifH
expression commenced 6–8 h later. The expression of all three genes was negatively affected by
addition of ammonia. Some early heterocyst differentiation genes were also identified in the genome
of Trichodesmium. The data suggest that hetR and ntcA may be required for development and
function of diazocytes in Trichodesmium. |
|
| dc.language |
en |
|
| dc.title |
Diurnal Expression of Hetr and Diazocyte Development in the Filamentous Non-Heterocystous Cyanobacterium Trichodesmium Erythraeum |
|
| dc.type |
Journal Article, Peer Reviewed |
|