The Chl-protein complexes of three maize (Zea mays L.) mutants and one barley (Hordeum vulgare L.) mutant were analyzed using low temperature Chl fluorescence emissions spectroscopy and LDS-polyacrylamide gel electrophoresis. The maize mutants hcf-3, hcf-19, and hcf-114 all exhibited a high Chl fluorescence (hc3') phenotype indicating a disruption of the energy transfer within the photosynthetic apparatus. The mutations in each of these maize mutants affects Photosystem II. The barley mutant analyzed was the well characterized Chl b-less mutant chlorina-f2, which did not exhibit the hcfphenotype. Chlorina-f2 was used because no complete Chl b-less mutant of maize is available. Analysis of hcf-3, hcf-19, and hcf-114 revealed that in the absence of CP43, LHC II can still transfer excitation energy to CP47. These results suggest that in mutant membranes LHC II can interact with CP47 as well as CP43. This functional interaction of LHC II with CP47 may only occur in the absence of CP43, however, it is possible that LHC II is positioned in the thylakoid membranes in a manner which allows association with both CP43 and CP47.
Abbreviations: h c fhigh chlorophyll fluorescence; LDS -lithium dodecyl sulfate; LHC II -light-harvesting complex of Photosystem II; LHC I -light-harvesting complex of Photosystem I; CPIa -chlorophyll-protein complex consisting of LHC I and the PSI core complex; CPI -chlorophyll-protein complex consisting of the PS I core complex; CP47 -47 kDa chlorophyll-protein of the Photosystem II core; CP43 -43 kDa chlorophyll-protein of the Photosystem II core; CP29 -29 kDa chlorophyll-protein of Photosystem II; CP26 -26 kDa chlorophyll-protein of Photosystem II; CP24 -24 kDa chlorophyll-protein of Photosystem II; fp -free pigments