The freshwater filamentous green oxyphotobacterium Prochlorothrix hollandica is an unusual oxygenic photoautotrophic cyanobacterium differing from most of the others by the presence of light-harvesting Pcb antenna binding both chlorophylls a and b and by the absence of phycobilins. The pigment-protein complexes of P. hollandica SAG 10.89 (CCAP 1490/1) were isolated from dodecylmaltoside solubilized thylakoid membranes on sucrose density gradient and characterized by biochemical, spectroscopic and immunoblotting methods. The Pcb antennae production is suppressed by high light conditions (>200 mumol photons m(-2) s(-1)) in P. hollandica. PcbC protein was found either in higher oligomeric states or coupled to PS I (forming antenna rings around PS I). PcbA and PcbB are most probably only very loosely bound to photosystems; we assume that these pigment-protein complexes function as low light-induced mobile antennae. Further, we have detected alpha-carotene in substantial quantities in P. hollandica thylakoid membranes, indicating the presence of chloroplast-like carotenoid synthetic pathway which is not present in common cyanobacteria.
- MeSH
- Electrophoresis, Polyacrylamide Gel MeSH
- Photosynthesis physiology MeSH
- Photosystem I Protein Complex isolation & purification metabolism MeSH
- Photosystem II Protein Complex isolation & purification metabolism MeSH
- Chromatography, Gel MeSH
- Immunoblotting MeSH
- Prochlorophytes metabolism MeSH
- Prochlorothrix metabolism MeSH
- Light MeSH
- Thylakoids metabolism ultrastructure MeSH
- Chromatography, High Pressure Liquid MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- MeSH
- Research Support as Topic MeSH
- Photosynthesis physiology MeSH
- Prochlorothrix chemistry metabolism MeSH
- Prokaryotic Cells metabolism MeSH
- Publication type
- Congress MeSH
