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Michael Reith - One of the best experts on this subject based on the ideXlab platform.
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a gametophyte cell wall protein of the red alga Porphyra purpurea rhodophyta contains four apparent polysaccharide binding domains1
Journal of Phycology, 1996Co-Authors: Neil W Ross, Pat Lanthier, Michael ReithAbstract:A complementary DNA(cDNA)clone from a Porphyra purpurea (Roth) C. Agardh gametophyte-specific subtracted cDNA library was found to encode a protein containing a signal peptide and four very similar regions with a high degree of amino acid sequence similarity to the cellulose-binding domains of fungal celluloses. Northern hybridization analysis indicated that the messenger RNA of this cDNA is highly abundant in the gametophyte but not detectable in the sporophyte. In vitro translation of the cDNA in the presence of canine pancreatic microsomes demonstrated that the signal peptide is capable of directing the protein into the endoplasmic reticulum where it is glycosylated. Because these observations suggested a possible role as a gametophyte-specific cell wall protein, cell wall protein, were isolated and a major protein having a molecular weight similar to that estimated for the encoded protein was purified. N-terminal sequence analysis indicated that this was the protein encoded by the cDNA. The abundance and organization of this protein suggest a role as a cell wall structural protein involved in cross-linking polysaccharides.
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A GAMETOPHYTE CELL WALL PROTEIN OF THE RED ALGA Porphyra purpurea (RHODOPHYTA) CONTAINS FOUR APPARENT POLYSACCHARIDE‐BINDING DOMAINS1
Journal of Phycology, 1996Co-Authors: Neil W Ross, Pat Lanthier, Michael ReithAbstract:A complementary DNA(cDNA)clone from a Porphyra purpurea (Roth) C. Agardh gametophyte-specific subtracted cDNA library was found to encode a protein containing a signal peptide and four very similar regions with a high degree of amino acid sequence similarity to the cellulose-binding domains of fungal celluloses. Northern hybridization analysis indicated that the messenger RNA of this cDNA is highly abundant in the gametophyte but not detectable in the sporophyte. In vitro translation of the cDNA in the presence of canine pancreatic microsomes demonstrated that the signal peptide is capable of directing the protein into the endoplasmic reticulum where it is glycosylated. Because these observations suggested a possible role as a gametophyte-specific cell wall protein, cell wall protein, were isolated and a major protein having a molecular weight similar to that estimated for the encoded protein was purified. N-terminal sequence analysis indicated that this was the protein encoded by the cDNA. The abundance and organization of this protein suggest a role as a cell wall structural protein involved in cross-linking polysaccharides.
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a sporophyte cell wall protein of the red alga Porphyra purpurea rhodophyta is a novel member of the chymotrypsin family of serine proteases1
Journal of Phycology, 1996Co-Authors: Michael ReithAbstract:A complementary DNA (cDNA) clone from a Porphyra purpurea (Roth) C. Agardh sporophyte-specific subtracted cDNA library was found to encode a protein similar to serine proteases of the chymotrypsin class. The encoded protein contains a typical signal peptide and is particularly similar to chymotrypsins in the regions surrounding the active site residues and the activation site where cleavage of the propeptide occurs. In addition, the six cysteine residues characteristic of chymotrypsins are conserved. However, two of the three residues of the active site His/Asp/Ser charge relay triad have been replaced, indicating that the protein is unlikely to have peptidase activity. Northern hybridization confirmed that this cDNA is derived from an abundant, sporophyte-specific messenger RNA (mRNA). The presence of signal peptide on the encoded protein and the abundance of its mRNA suggested that this protein might be localized in the cell wall. Consequently, sporophyte cell walls were isolated and a major protein having a molecular weight similar to that estimated for the encoded protein was purified. N-terminal sequence analysis indicated that this cell wall protein is identical to that encoded by the cDNA with the amino terminus of the mature protein beginning at the activation site. This cell wall structural protein appears to have evolved from a chymotrypsin-like progenitor but has been adapted to bind cell wall proteins and/or polysaccharides rather than to cleave proteins.
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Complete nucleotide sequence of thePorphyra purpurea chloroplast genome
Plant Molecular Biology Reporter, 1995Co-Authors: Michael Reith, Janet MunhollandAbstract:The complete nucleotide sequence of the chloroplast genome of the red alga Porphyra purpurea has been determined (accession number=U38804). The circular genome is 191,028 bp in length and encodes approximately 250 genes.
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isolation and characterization of phase specific complementary dnas from sporophytes and gametophytes of Porphyra purpurea rhodophyta using subtracted complementary dna libraries1
Journal of Phycology, 1994Co-Authors: John P Van Der Meer, Michael ReithAbstract:The red alga Porphyra purpurea (Roth) C. Agardh has a life cycle that alternates between shell-boring, filamentous sporophytes and free-living, foliose gametophytes. The significant morphological differences between these two phases suggest that many genes should be developmentally regulated and expressed in a phase-specific manner. In this study, we prepared and screened subtracted complementary DNA (cDNA) libraries specific for the sporophyte and gametophyte of P. purpurea. This involved the construction of cDNA libraries from each phase, followed by the removal of common clones through subtractive hybridization. Sampling of the subtracted libraries indicated that 8–10% of the recombinant colonies in each library were specific for the appropriate phase. Of 20 putative phase-specific cDNAs selected from each subtracted library, eight unique clones were obtained for the sporophyte and seven for the gametophyte. After confirming their phase-specificities by hybridization to gametophyte and sporophyte messenger RNA, these 15 phase-specific cDNAs were sequenced, and the deduced amino acid sequences were used to search protein databanks. Two proteins encoded by the sporophyte-specific cDNAs and two by the gametophyte-specific cDNAs were identified by their similarity to databank entries.
Franz B Lang - One of the best experts on this subject based on the ideXlab platform.
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complete sequence of the mitochondrial dna of the red alga Porphyra purpurea cyanobacterial introns and shared ancestry of red and green algae
The Plant Cell, 1999Co-Authors: Gertraud Burger, Diane Saintlouis, Michael W Gray, Franz B LangAbstract:The mitochondrial DNA (mtDNA) of Porphyra purpurea , a circular-mapping genome of 36,753 bp, has been completely sequenced. A total of 57 densely packed genes has been identified, including the basic set typically found in animals and fungi, as well as seven genes characteristic of protist and plant mtDNAs and specifying ribosomal proteins and subunits of succinate:ubiquinone oxido-reductase. The mitochondrial large subunit rRNA gene contains two group II introns that are extraordinarily similar to those found in the cyanobacterium Calothrix sp, suggesting a recent lateral intron transfer between a bacterial and a mitochondrial genome. Notable features of P. purpurea mtDNA include the presence of two 291-bp inverted repeats that likely mediate homologous recombination, resulting in genome rearrangement, and of numerous sequence polymorphisms in the coding and intergenic regions. Comparative analysis of red algal mitochondrial genomes from five different, evolutionarily distant orders reveals that rhodophyte mtDNAs are unusually uniform in size and gene order. Finally, phylogenetic analyses provide strong evidence that red algae share a common ancestry with green algae and plants.
Janet Munholland - One of the best experts on this subject based on the ideXlab platform.
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Complete nucleotide sequence of thePorphyra purpurea chloroplast genome
Plant Molecular Biology Reporter, 1995Co-Authors: Michael Reith, Janet MunhollandAbstract:The complete nucleotide sequence of the chloroplast genome of the red alga Porphyra purpurea has been determined (accession number=U38804). The circular genome is 191,028 bp in length and encodes approximately 250 genes.
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the ribosomal rna repeats are non identical and directly oriented in the chloroplast genome of the red alga Porphyra purpurea
Current Genetics, 1993Co-Authors: Michael Reith, Janet MunhollandAbstract:A detailed restriction map of the chloroplast genome of the red alga Porphyra purpurea has been constructed. Southern hybridization experiments with cloned or gel-purified restriction fragments and PCR products indicate that the P. purpurea chloroplast genome is approximately 188 kb in size. This circular molecule contains two rRNA-encoding repeats (approximately 4.9 kb) that separate the genome into single-copy regions of 34 kb and 144 kb. Interestingly, these repeats are arranged in a direct orientation. In addition, DNA sequencing of the ends of both repeats revealed that the two rRNA repeats are not identical. No intramolecular recombination between the repeats can be detected. We discuss the possibility that the chloroplast genome of P. purpurea is organized like that of the ancestral chloroplast.
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a high resolution gene map of the chloroplast genome of the red alga Porphyra purpurea
The Plant Cell, 1993Co-Authors: Michael Reith, Janet MunhollandAbstract:Extensive DNA sequencing of the chloroplast genome of the red alga Porphyra purpurea has resulted in the detection of more than 125 genes. Fifty-eight (approximately 46%) of these genes are not found on the chloroplast genomes of land plants. These include genes encoding 17 photosynthetic proteins, three tRNAs, and nine ribosomal proteins. In addition, nine genes encoding proteins related to biosynthetic functions, six genes encoding proteins involved in gene expression, and at least five genes encoding miscellaneous proteins are among those not known to be located on land plant chloroplast genomes. The increased coding capacity of the P. purpurea chloroplast genome, along with other characteristics such as the absence of introns and the conservation of ancestral operons, demonstrate the primitive nature of the P. purpurea chloroplast genome. In addition, evidence for a monophyletic origin of chloroplasts is suggested by the identification of two groups of genes that are clustered in chloroplast genomes but not in cyanobacteria.
Jeffrey W Gallant - One of the best experts on this subject based on the ideXlab platform.
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β tubulin gene of Porphyra purpurea rhodophyta
Journal of Phycology, 2002Co-Authors: Ron M Mackay, Jeffrey W GallantAbstract:The life cycle of the marine red alga Porphyra purpurea (Roth) C. Agardh includes a shell-boring filamentous sporophyte and a leafy gametophyte. A single intronless gene for the microtubule protein β-tubulin was discovered by molecular cloning of P. purpurea cDNA and genomic DNA. This gene, named TubB1, encodes a β-tubulin with a divergent amino acid sequence, showing 74% identity with the conserved β-tubulin of Chlamydomonas reinhardtii P. A. Dangeard. Southern hybridization analysis of nuclear DNA confirmed that P. purpurea has a single TubB1 gene. Transcripts (1.8 kb) of TubB1 are present in the sporophyte and gametophyte. Codon bias indicates strong expression of TubB1. The divergent nature of the TubB1 genes suggests that the absence of axonemal structures has allowed substantial genetic drift in red algal β-tubulin genes.
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β‐TUBULIN GENE OF Porphyra purpurea ( RHODOPHYTA)
Journal of Phycology, 2002Co-Authors: Ron M Mackay, Jeffrey W GallantAbstract:The life cycle of the marine red alga Porphyra purpurea (Roth) C. Agardh includes a shell-boring filamentous sporophyte and a leafy gametophyte. A single intronless gene for the microtubule protein β-tubulin was discovered by molecular cloning of P. purpurea cDNA and genomic DNA. This gene, named TubB1, encodes a β-tubulin with a divergent amino acid sequence, showing 74% identity with the conserved β-tubulin of Chlamydomonas reinhardtii P. A. Dangeard. Southern hybridization analysis of nuclear DNA confirmed that P. purpurea has a single TubB1 gene. Transcripts (1.8 kb) of TubB1 are present in the sporophyte and gametophyte. Codon bias indicates strong expression of TubB1. The divergent nature of the TubB1 genes suggests that the absence of axonemal structures has allowed substantial genetic drift in red algal β-tubulin genes.
Gertraud Burger - One of the best experts on this subject based on the ideXlab platform.
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complete sequence of the mitochondrial dna of the red alga Porphyra purpurea cyanobacterial introns and shared ancestry of red and green algae
The Plant Cell, 1999Co-Authors: Gertraud Burger, Diane Saintlouis, Michael W Gray, Franz B LangAbstract:The mitochondrial DNA (mtDNA) of Porphyra purpurea , a circular-mapping genome of 36,753 bp, has been completely sequenced. A total of 57 densely packed genes has been identified, including the basic set typically found in animals and fungi, as well as seven genes characteristic of protist and plant mtDNAs and specifying ribosomal proteins and subunits of succinate:ubiquinone oxido-reductase. The mitochondrial large subunit rRNA gene contains two group II introns that are extraordinarily similar to those found in the cyanobacterium Calothrix sp, suggesting a recent lateral intron transfer between a bacterial and a mitochondrial genome. Notable features of P. purpurea mtDNA include the presence of two 291-bp inverted repeats that likely mediate homologous recombination, resulting in genome rearrangement, and of numerous sequence polymorphisms in the coding and intergenic regions. Comparative analysis of red algal mitochondrial genomes from five different, evolutionarily distant orders reveals that rhodophyte mtDNAs are unusually uniform in size and gene order. Finally, phylogenetic analyses provide strong evidence that red algae share a common ancestry with green algae and plants.