Chlorophyll-protein complexes. Variability of CPI, and the existence of two distinct forms of LHCP and one low-molecular-weight chlorophyll a protein

Relation between the Light-Harvesting Chlorophyll a-Protein Complex LHCPa and Photosystem I in the Alga Chlamydobotrys stellata

“…This leads to changes in PSII activity (15,16), almost grana-free chloroplasts (25,26), and to a decrease in the PSII-dependent electron transport to PSI (27). Furthermore, phototrophic acetate nutrition induces an increase in the amount of Chl-protein complex LHCPa2 containing Chl a only (8). This work presents evidence for the relation of LHCPa to PSI.…”

“…The polypeptide composition of the Chl-protein complexes III and IV separated by SDS-PAGE after PAGIF is shown in Figure 3. As detected by high-sensitive silver staining (18), the dominant polypeptides of 6 As previously reported from this laboratory, the Chl-proteid IV most likely functions as the light-harvesting system LHCPb of PSII (8). No information is as yet available about the relation of the Chl-protein complex III to the photosynthetic apparatus.…”

“…Only band IV shows Chl b as identified by the absorption maximum at 654 nm. This complex is identified as the known LHCPb of C. stellata (8). However, these absorption maxima determined in detergent-containing media do not represent the absorption properties of the in vivo Chl-proteids (20).…”

“…For PAGIF, the method of Siefermann-Harms and Ninnemann (21) was used. Absorption spectra of Chl-protein complexes were recorded as previously described (8).…”

Induction of the De Novo Formation of the Photosystem I-Related Light-Harvesting Chlorophyll Protein Complex LHCPa by Photoheterotrophic Nutrition

“…Only the LHCPb is comparable with the LHCP of higher plants, whereas the PSI-related LHCPa of C. stellata is not comparable with the CPIa described in spinach (1), pea (8), or Chlamydomonas reinhardii (9). Moreover, the CPIa functioning as light-harvesting system for PSI in higher plants is absent in C. stellata (5). Under photoheterotrophic conditions, therefore, the loss of LHCPb, which supplies PSII and PSI with energy (3) in autotrophically grown Chiamydobotrys cells, is compensated by the de novo formation ofthe LHCPa, which is an integrated component of the PSI in C. stellata (6).…”