| Value |
24000
molecules/cell
|
| Organism |
Bacterioplankton SAR86 |
| Reference |
Béjà O, Spudich EN, Spudich JL, Leclerc M, DeLong EF. Proteorhodopsin phototrophy in the ocean. Nature. 2001 Jun 14411(6839):786-9PubMed ID11459054
|
| Method |
Antarctic coastal waters were collected. Cell membranes were prepared from picoplankton cells concentrated from surface seawater.Fluorescence in situ hybridization BAC clones 31A08 and 27G05 (ref. 10) were used as templates to generate SAR86-specific polyribonucleotide probes targeted to large-subunit ribosomal RNA. |
| Comments |
Assuming (1) the flash yield of the environmental pigment is similar to that of proteorhodopsin expressed in E. coli, (2) a molar absorption coefficient of 50000 M^-1*cm^-1 at the absorption maximum (see bion 103733), (3) fluorescence in situ hybridization counts of a total of 5.6e+10 SAR86 cells in the concentrated sample (~10% of the total bacteria see methods), (4) 50% of recovery of membranes from the cells, and (5) that the uncultivated SAR86 group is the principal bacterioplankton group using these pigments, researchers calculate that there are 24000 proteorhodopsin molecules per SAR86 cell. |
| Entered by |
Uri M |
| ID |
103734 |