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1.
The amino acid sequence of a ferredoxin from a unicellular blue-green alga, Aphanothece halophitica, was established by the conventional methods. Total number of residues was 98 lacking only tryptophan. A most probable phylogenetic tree was constructed for 19 algal ferredoxins on the basis of an amino acid difference matrix made from the sequence comparison. A. halophitica has been classified as a unicellular blue-green alga in the same genus to which Aphanothece sacrum belongs, but the tree indicates A. halophitica ferredoxin to be very close to those of the members of filamentous blue-green algae. The tree divides prokaryotic and eukaryotic algal ferredoxins into several groups, suggesting that the ferredoxin phylogenetic tree reflects the evolutionary trails of various algae, which is also reflected in the structural characteristics, particularly in the presence of gaps. Other notable features are presented in considering algal taxonomy.  相似文献   

2.
The amino acid sequence of a [2Fe-2S] ferredoxin from a red alga, Rhodymenia palmata in the family Florideophyceae, was determined by conventional methods. The ferredoxin is composed of 97 amino acid residues having five cysteines, but lacking methionine and tryptophan. It possesses a number of structural features of particular interest. The amino acid sequence is compared with those previously determined for ferredoxins from two red algae in the family Bangiophyceae. Conclusions from a comparison of the structures, by noting features such as the presence of gaps in the sequences and by constructing a phylogenetic tree, were consistent with the proposed taxonomic relationship among these algae.  相似文献   

3.
The amino acid sequence of ferredoxin from Synechocystis 6714, a unicellular blue-green alga, was determined by a combination of conventional methods. The ferredoxin was composed of 96 amino acid residues and lacked methionine and tryptophan. The sequence was as follows: Ala-Ser-Tyr-Thr-Val-Lys-Leu-Ile-Thr- Pro-Asp-Gly-Glu-Asn-Ser-Ile-Glu-Cys-Ser-Asp-Asp-Thr-Tyr-Ile-Leu-Asp-Ala-Ala- Glu-Glu-Ala-Gly-Leu-Asp-Leu-Pro-Tyr-Ser-Cys-Arg-Ala-Gly-Ala-Cys-Ser-Thr-Cys- Ala-Gly-Lys-Ile-Thr-Ala-Gly-Ser-Val-Asp-Gln-Ser-Asp-Gln-Ser-Phe-Leu-Asp-Asp- Asp-Gln-Ile-Glu-Ala-Gly-Tyr-Val-Leu-Thr-Cys-Val-Ala-Tyr-Pro-Thr-Ser-Asp-Cys-Thr-Ile-Glu-Thr-His-Lys-Glu-Glu-Asp-Leu-Tyr. In an alignment of various ferredoxins with high homology from unicellular and filamentous blue-green algae, Synechocystis 6714 ferredoxin showed 4 gaps. Those between residues 9 and 10 and between residues 12 and 13 were unique for the ferredoxins from the unicellular algae Synechocystis 6714 and Aphanothece sacrum (ferredoxin I). Therefore, ferredoxins from unicellular algae were distinguishable from those of filamentous algae in terms of the presence of gaps. This feature appears to coincide with the phylogenetic division between the two types of blue-green algae.  相似文献   

4.
The amino acid sequence of the ferrodoxin of Porphyra umbilicalis was determined by the dansyl-phenyl isothiocyanate method, on peptides obtained by tryptic, chymotryptic and thermolytic digestion of the protein or its CNBr-cleavage fragments. The molecule consists of 98 residues, has an unblocked N-terminus and shows considerable similarity with other plant-type ferredoxins. It is the first reported sequence of a red-algal ferredoxin.  相似文献   

5.
NADP:ferredoxin oxidoreductase (EC. 1.6.7.1.) isolated from a thermophilic blue-green alga, Synechococcus sp., was stable at temperatures up to 65°C. The diaphorase and cytochrome c reductase activities of the enzyme were low at 25°C but increased with elevated temperature to reach a maximum at about 60°C. The pH-profile of the diaphorase activity showed a peak at pH 9.0 at 55°C, whereas the activity was largely independent of pH at 25°C. High concentrations of NaCl suppressed activity at both high and low temperatures. In the cytochrome c reductase activity catalyzed by the enzyme, ferredoxin served as an electron carrier in a temperature-insensitive manner over a wide range of temperature. The results support the view that the optimum and the upper limiting temperatures for photosynthesis in this alga are related to thermal properties of proteins.  相似文献   

6.
7.
Two C-type cytochromes and ferredoxin were isolated and purifiedfrom the thermophilic blue-green alga Synechococcus sp. Theirheat-stabilities were studied in relation to the thermophilyof the alga. (Received May 23, 1979; )  相似文献   

8.
9.
Summary The fatty acids of 32 axenic strains of filamentous blue-green algae have been analyzed. As an aid to the interpretation of the results, the strains have been assigned to provisional typological groups based upon their morphology and certain physiological characters. The latter are the ability to grow heterotrophically in the dark with glucose as carbon and energy source, the ability to grow in the light at the expense of glucose in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), and the ability to synthesize nitrogenase under anaerobic conditions in the light. Each typological group has been given an appropriate generic name.The strains examined for fatty acid composition can be divided into groups according to the major fatty acid of highest degree of unsaturation found in each strain as was done for the unicellular strains examined previously in this laboratory. Four metabolic groups of strains of unicellular and filamentous blue-green algae can be recognized: 1. those in which there is little or no desaturation of oleate; 2. those in which linoleate is desaturated toward the -end of the molecule to give -linolenate; 3. those in which linoleate is desaturated toward the carboxyl end of the molecule to give -linolenate; 4. those in which octadecatetraenoate is synthesized. The nature of the major cellular fatty acids of two of the strains examined is the same whether growth is in the light or in the dark on glucose. All filamentous strains contain glycolipids with the properties of mono- and digalactosyldiglycerides.Abbreviation DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea  相似文献   

10.
A ferredoxin was purified as the pure state from a club moss (Lycopodium clavatum L.) and sequenced. The ferredoxin was composed of 99 amino acids and had a molecular mass of 10,728, excluding iron and sulfur atoms. The ferredoxin sequence was rather distinct from that fromMarchantia polymorpha, Equisetum andGleichenia japonica. Based on comparison of ferredoxin sequences thus far established, the phylogenetic relationship between lower vascular plants is discussed.  相似文献   

11.
1. The primary structure of a 4Fe-4S ferredoxin from Bacillus stearothermophilus was determined and shown to consist of a single polypeptide chain of 81 amino acid residues. The molecular weight of the holoprotein is about 9120. 2. There are only four cysteine residues in the molecule; three of these are located near the N-terminus as a Cys-X-X-Cys-X-X-Cys segment, and the fourth cysteine residue is followed by a proline and located in the C-terminal half. 3. The Fe-S chromophore in B. stearothermophilus ferredoxin was previously well characterized and was shown to consist of a single 4Fe-4S cluster. This ferredoxin sequence establishes for the first time the relative location of the four cysteine residues necessary to bind the 4Fe-4S cluster of a 4Fe ferredoxin, and is in agreement with the criteria for the relative positions of the cysteines proposed from X-ray-crystallographic studies on an 8Fe (two 4Fe-4S clusters) ferredoxin. 4. The sequence of B. stearothermophilus ferredoxin is homologous in many segments to that of other bacterial ferredoxins, the degree of homology being greater towards ferredoxins from Desulfovibrio gigas and photosynthetic bacteria than to Clostridial ferredoxins. 5. The presence of a relatively higher number of glutamic acid and lower number of cysteine residues in the molecule may explain the greater thermal stability and oxygen-insenstivity of this ferredoxin.  相似文献   

12.
Amino acid sequence of Desulfovibrio gigas ferredoxin: revisions   总被引:1,自引:0,他引:1  
Reexamination of the amino acid sequence of Desulfovibriogigas ferredoxin revealed that the sequence published in 1971 should be revised. This sequence was determined using automatic protein sequencer in liquid phase and in solid phase. Peptides derived from tryptic hydrolysis, Staphylococcusaureus protease hydrolysis, cyanogen bromide cleavage were used to construct the total sequence. This ferredoxin contains 6 cysteines per minimum molecular weight of 6,400. 4 cysteines are linked to a (4 Fe-4 S) cluster and the two others possibly participate in a disulfide bridge.  相似文献   

13.
Amino acid sequence of ferredoxin I from Desulfovibrio vulgaris Miyazaki   总被引:1,自引:0,他引:1  
The amino acid sequence of ferredoxin (Fd) I, purified from Desulfovibrio vulgaris Miyazaki, has been established. Fd I is strikingly similar to Fd III of D. africanus Benghazi with 84% homology. Both have the sequence, -Cys-x-x-Asp-x-x-Cys-x-x-x-Cys-Pro- in the N-terminal half, and the sequence, -Cys-x-x-Cys-x-x-Cys-x-x-x-Cys-Glu- in the C-terminal half of the molecule, instead of the common sequences for ligation to the usual [4Fe-4S] clusters. Fd I has 76% homology to Fd II of D. desulfuricans Norway.  相似文献   

14.
Ferredoxin from Arctium lappa consists of a single polypeptide chain of 97 residues, four of which are cysteine. These residues, which are in the active centre, are in identical positions to those of other ferredoxins. Overlap between residue positions 50/51 was not obtained, but amino acid composition of the two cyanogen bromide fragments which were overlapped corresponded with the amino acid composition of the total protein.  相似文献   

15.
The complete sequence of amino acids of ferredoxin II (FdII) from Rhodospirillum rubrum was determined by repetitive Edman degradation using pyridylethylated-ferredoxin and oxidized, denatured ferredoxin. Peptides derived from trypsin, pepsin, Glu-C endoproteinase, Arg-C endoproteinase, tryptophan specific cleavage and partial acid hydrolysis and C-terminal sequence from carboxypeptidase digestion were used to construct the total sequence. RrFdII is a polypeptide of 104 amino acids having a calculated molecular weight of 11556 excluding the iron and sulfur atoms. The complete amino acid sequence was: PYVVTENCIKCKYQDCVEVCPVDCFYEGENFLVINPDECIDCGVCNPECPAEAIAGKWLEINRKFADLWPNITRKGPAL ADADDWKDKPDKTGLLSENPGKGTV. Sequence comparisons, EPR characteristics and iron analyses indicate that RrFdII has structural features in common with ferredoxins containing [3Fe-4S], [4Fe-4S] centers. Of 104 amino acids, 60 (58%) including all 9 cysteines, are found in identical locations in the 7Fe ferredoxin prototype, Azotobacter vinelandii FdI.The protein sequence data reported in this paper will appear in the SWISS-PROT database and EMBL Data Library under the accession number P80448.  相似文献   

16.
Filamentous mutants were induced in a coccoid blue-green alga, Agmenellum quadruplicatum strain BG1, after treatment with N-methyl-N'-nitro-N-nitrosoguanidine (NTG). The mutants fall into two general classes: filaments with cross walls and filaments without cross walls. All mutants of these general types derived from BG1 are stable and have growth rates the same as or very similar to the wild type under a variety of conditions. Detailed examination of one mutant, 53SB2, revealed no difference in deoxyribonucleic acid content nor in base ratios. Mutant 53SB2 did not revert to the normal cell size and shape when grown under different physical conditions nor upon the addition of potential reversing agents to the basal medium. It is our general experience that filamentous mutants such as those described here in BG1 are commonly induced in other coccoid blue-green algae after NTG treatment.  相似文献   

17.
The ferredoxin was purified from the green alga, Chlamydomonas reinhardtii. The protein showed typical absorption and circular dichroism spectra of a [2Fe-2S] ferredoxin. When compared with spinach ferredoxin, the C. reinhardtii protein was less effective in the catalysis of NADP+ photoreduction, but its activity was higher in the light activation of C. reinhardtii malate dehydrogenase (NADP). The complete amino acid sequence was determined by automated Edman degradation of the whole protein and of peptides obtained by trypsin and chymotrypsin digestions and by CNBr cleavage. The protein consists of 94 residues, with Tyr at both NH2 and COOH termini. The positions of the four cysteines binding the two iron atoms are similar to those found in other [2Fe-2S] ferredoxins. The primary structure of C. reinhardtii ferredoxin showed a great homology (about 80%) with ferredoxins from two other green algae.  相似文献   

18.
Amino acid sequence of spinach ferredoxin:NADP+ oxidoreductase   总被引:9,自引:0,他引:9  
The amino acid sequence of spinach ferredoxin: NADP+ oxidoreductase was determined by using overlapping sets of peptides derived by cleavage at arginyl or methionyl residues. The protein from different preparations varied in its length at the amino terminus. In the longest form the amino terminus is blocked with a pyroglutamyl residue, as determined by NMR. A single disulfide bond was placed between cysteine residues 132 and 137. The 314-residue sequence corresponds to a molecular weight of 35 317. The carboxyl-terminal half of the sequence has been fit to the electron density map of the NADP binding domain, revealing that this portion of the chain forms a typical nucleotide binding fold.  相似文献   

19.
The present-day concepts on phycobiliproteins, the protein pigments of blue-green, red and cryptophyte algae are reviewed. The functions, distribution, localization, physico-chemical, spectral and immunochemical properties of phycobiliproteins are described. The properties of the polypeptide protein subunits and the composition and chemical structure of chromophores as well as their binding to the apoprotein molecules are discussed.  相似文献   

20.
The amino acid sequence of Chlorogloeopsis fritschii ferredoxin was determined for its carboxymethylated derivative by using solid-phase sequencing, fragmentation with various enzymes, and manual Edman degradation procedures. The ferredoxin was composed of 98 amino acid residues and lacked methionine and tryptophan. The sequence was as follows: Ala-Thr-Tyr-Lys-Val-Thr-Leu-Ile-Asn-Asp-Ala-Glu- Gly-Leu-Asn-Gln-Thr-Ile-Glu-Val-Asp-Asp-Asp-Thr-Tyr-Ile-Leu-Asp-Ala-Ala-Glu- Glu-Ala-Gly-Leu-Asp-Leu-Pro-Tyr-Ser-Cys-Arg-Ala-Gly-Ala-Cys-Ser-Thr-Cys-Ala-Gly-Lys-Ile-Lys-Ser-Gly-Thr-Val-Asp-Gln-Ser-Asp-Gln-Ser-Phe-Leu-Asp-Asp-Asp- Gln-Ile-Glu-Ala-Gly-Tyr-Val-Leu-Thr-Cys-Val-Ala-Tyr-Pro-Thr-Ser-Asp-Cys-Thr-Ile-Glu-Thr-His-Lys-Glu-Glu-Glu-Leu-Tyr. A phylogenetic tree was constructed on the basis of a comparison of various algal ferredoxins and it was found that C. fritschii ferredoxin was closely related to Mastigocladus laminosus ferredoxin, though they are in different genera of the blue-green algae. Aspects of the taxonomy and molecular evolution of blue-green algal ferredoxins are discussed.  相似文献   

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