Development at Cold-Hardening Temperatures 1: The Structure and Composition of Purified Rye Light Harvesting Complex II
AUTOR(ES)
Krupa, Zbigniew
RESUMO
Light harvesting complex II (LHCII) was purified from cold-hardened (RH) and nonhardened winter rye (RNH) (Secale cereale L. cv Puma) employing a modified procedure of JJ Burke, CL Ditto, CJ Arntzen (Arch Biochem Biophys 187: 252-263). Triton X-100 solubilization of thylakoid membranes followed by three successive precipitations with 100 mm KCl and 10 mm MgCl2 resulted in yields of up to 25% on a chlorophyll (Chl) basis and a purity of 90 to 95%, based on polypeptide analysis within 4 hours. Polypeptide and pigment analyses, 77 K fluorescence emission and room temperature absorption spectra indicate the LHCII obtained by this modified method is comparable to LHCII obtained by other published methods. Comparison of purified RH and RNH LHCII indicated no significant differences with respect to polypeptide, amino acid, Chl, and carotenoid compositions as well as no differences in lipid content. However, RH LHCII differed from RNH LHCII specifically with respect to the fatty acid composition of phosphatidyldiacylglycerol only. RH LHCII exhibited a 54% lower trans-Δ3-hexadecenoic acid level associated with PG and a 60% lower oligomeric LHCII:monomeric LHCII (LHCII1:LHCII3) than RNH LHCII. Both RH and RNH LHCII exhibited a 5-fold enrichment in PG specifically. Complete removal of PG by enzymic hydrolysis resulted in a significant reduction in the oligomeric content of both RH and RNH LHCII such that LHCII1:LHCII3 of RH and RNH LHCII preparations were the same. This confirms that this specific compositional change accounts for the structural differences between RH and RNH LCHII observed in situ and in vitro.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1056520Documentos Relacionados
- Composition of photosystem II antenna in light-harvesting complex II antisense tobacco plants at varying irradiances.
- Effect of Cold Hardening on the Components of Respiratory Decarboxylation in the Light and in the Dark in Leaves of Winter Rye.
- Appearance of type 1, 2, and 3 light-harvesting complex II and light-harvesting complex I proteins during light-induced greening of barley (Hordeum vulgare) etioplasts.
- AtFtsH6 is involved in the degradation of the light-harvesting complex II during high-light acclimation and senescence
- Polysomes from Winter Rye Seedlings Grown at Low Temperature 1: I. Size Class Distribution, Composition, and Stability