A KDP-LIKE, HIGH-AFFINITY, K+-TRANSLOCATING ATPASE IS EXPRESSED DURING GROWTH OF RHODOBACTER-SPHAEROIDES IN LOW POTASSIUM MEDIA - DISTRIBUTION OF THIS K+-ATPASE AMONG PURPLE NONSULFUR PHOTOTROPHIC BACTERIA
Autor(en): | ABEE, T KNOL, J HELLINGWERF, KJ BAKKER, EP SIEBERS, A KONINGS, WN |
Stichwörter: | ESCHERICHIA-COLI; EXPRESSION; HIGH-AFFINITY TRANSPORT SYSTEM; IMMUNOLOGICAL CROSS-REACTIVITY; INTERNAL PH REGULATION; IONS; KDP-LIKE POTASSIUM ATPASE; Microbiology; PH; PHOTOSYNTHETIC BACTERIA (RHODOBACTER-SPHAEROIDES, RHODOBACTER-CAPSULATUS AND RHODOSPIRILLUM-RUBRUM); POTASSIUM TRANSPORT; PROTEINS; RHODOPSEUDOMONAS-SPHAEROIDES; TRANSPORT ATPASES | Erscheinungsdatum: | 1992 | Herausgeber: | SPRINGER | Enthalten in: | ARCHIVES OF MICROBIOLOGY | Band: | 158 | Ausgabe: | 5 | Startseite: | 374 | Seitenende: | 380 | Zusammenfassung: | Cells of the purple non-sulphur bacterium Rhodobacter sphaeroides express a high-affinity K+ uptake system when grown in media with low K+ concentrations. Antibodies against the catalytic KdpB protein or the whole KdpABC complex of Escherichia coli cross-react with a 70.0 kDa R. sphaeroides protein that was expressed only in cells grown in media with low K+ concentrations. In membranes derived from R. sphaeroides cells grown with low K+ concentrations (induced cells), a high ATPase activity could be detected when assayed in Tris-HCI pH 8.0 containing 1 mM MgSO4. This ATPase activity increased upon addition of 1 mM KCl from 166 to 289 mumol ATP hydrolysed x min-1 x g protein-1 (1.7-fold stimulation). The K+-stimulated ATPase activity was inhibited approximately 93% by 0.5 mM vanadate but hardly by NN-dicyclohexylcarbodiimide (DCCD). These results indicate that the inducible K+-ATPase in R. sphaeroides resembles the Kdp K+-translocating ATPase of Escherichia coli. This Kdp-like transport system is also expressed in R. capsulatus and Rhodospirillum rubrum during growth in media with low K+ concentrations suggesting a wide distribution of this transport system among phototrophic bacteria. |
ISSN: | 03028933 | DOI: | 10.1007/BF00245368 |
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geprüft am 05.06.2024