RESUMO
The structure of the rye chloroplast DNA which contains the psbK gene coding for a subunit of photosystem II is determined. The gene psbI encoding an other protein of photosystem II is located 407 bp downstream from the stop codon of this gene. The determination of structure of the intergenic region between the psbI and psbD genes is fully elucidated. The rye BamHI fragment, comprising the psbK gene, is structurally similar to the corresponding fragment of the barley genome.
Assuntos
Complexo de Proteínas do Centro de Reação Fotossintética/genética , Secale/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Cloroplastos/metabolismo , DNA , Dados de Sequência Molecular , Complexo de Proteína do Fotossistema IIRESUMO
Structures of the rye chloroplast DNA regions, containing psbD and psbI genes coding for the components of the reaction centre of photosystem II, D2 protein and I polypeptide, respectively, have been determined. The gene trnS for tRNA(Ser) (GCU) is located 111 bp downstream from the stop codon of the psbI gene on the opposite strand. The high homology between the rye BamHI-fragment comprising these genes and his counterpart from wheat are discussed.
Assuntos
Complexo de Proteínas do Centro de Reação Fotossintética/genética , Secale/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Cloroplastos , DNA/genética , Dados de Sequência Molecular , Complexo de Proteína do Fotossistema II , Proteínas de Plantas/genética , Plasmídeos , Mapeamento por Restrição , Homologia de Sequência do Ácido NucleicoRESUMO
The structure of the rye chloroplast DNA, which contains psbC gene coding for 43-kDa chlorophyll(a)-binding subunit of photosystem II, is determined. The sequence of trnS (UGA) gene encoding tRNA Ser is located at a distance of 140 bp downstream from the stop codon of psbC gene on the opposite DNA strand. The 5'-terminal part of psbC gene, like in other plants, overlaps by 50 bp the 3'-terminal region of psbD gene coding for D2 protein of photosystem II. The amino acid sequence of the psbC gene product reveals common features with the structure of the psbB gene product (CPa-1 protein). The structural similarity of these two proteins seems to reflect their similar functions.
Assuntos
Clorofila/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Proteínas/metabolismo , Secale/genética , Sequência de Aminoácidos , Clorofila/genética , Clorofila A , Cloroplastos/metabolismo , Códon , DNA/genética , Complexos de Proteínas Captadores de Luz , Dados de Sequência Molecular , Complexo de Proteína do Fotossistema II , Proteínas/genética , Homologia de Sequência do Ácido NucleicoRESUMO
EcoRI and BamHI fragments of rye chloroplast DNA comprising psbA gene were cloned and a 2729 bp region was sequenced. Cloning of EcoRI fragment into pTZ19R plasmid led to a single nucleotide deletion in the coding region of psbA gene. A scheme of full-length psbA gene cloning is proposed, allowing one to escape the damage effect of the psbA gene expression product on the host cell. The differences between monocot and dicot in nucleotide sequences of DNA downstream of psbA genes are discussed. Gene rps19 is located 131 bp downstream from psbA gene on the complementary strand. The amino acid sequences of D1 and S19 proteins of different species are compared.
Assuntos
Cloroplastos/química , DNA/genética , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Complexo de Proteína do Fotossistema II , Mapeamento por Restrição , SecaleRESUMO
The primary structure of the 1084 bp AccI-BamHI fragment of rye chloroplast DNA containing psbE, psbF and psbL genes and ORF40 with their flanking and intergenic regions is elucidated.
Assuntos
Clorofila/genética , Cloroplastos , DNA/genética , Grão Comestível/genética , Proteínas de Plantas/genética , Secale/genética , Sequência de Aminoácidos , Sequência de Bases , Complexos de Proteínas Captadores de Luz , Dados de Sequência Molecular , Complexo de Proteínas do Centro de Reação Fotossintética , Complexo de Proteína do Fotossistema IIRESUMO
Chloroplast DNA was isolated from rye seedlings by the non-aqueous method. The region of rye ctDNA which comprises two genes psbB and psbH encoding polypeptide subunits of photosystem II (47 kappa l) Chl alpha -binding protein (CP alpha -1) and 10 kD phosphoprotein, respectively) and two ORFs in the opposite strands in the psbB--psbH spacer region encoding hydrophobic peptides with strongly charged C-terminal segments was sequenced. The deduced amino acid sequences of polypeptide products of the genes were compared with those of different plant species (in case of the psbB product also with sequence of a cyano-bacterium Synechocystis) and revealed some highly conservative amino acid residues and regions of polypeptide chains, which apparently play essential role in the interaction with other PS II subunits and in the binding of chlorophyll molecules. Some speculations are made on the possible function of the peptides encoded by the two ORFs.
