A cDNA sequence of phosphopyruvate hydratase (enolase) from Black Tiger Prawn, Penaeus monodon
Chanikarn Boonchuoy1, Boonyaruk Boonyawan2, Sakol Panyim2,
and Burachai Sonthayanon*1,2
1Central Equipment Laboratory, Institute of Science and Technology for Research and Development, Mahidol University,
Salaya Campus, and 2Institute of Molecular Biology and Genetics, Mahidol University, Salaya Campus,
Phutthamonthon 4 Rd., Phutthamonthon District, Nakhon Pathom 73170, Thailand
(Received 17 December 1998 / Accepted 23 March 1999)
Abstract.
A sequence determination was performed on a 1.86. kb cDNA clone designated as PMM020. The clone was among a set of random cDNA clones isolated from an abdominal muscle cDNA library of Black Tiger Prawn which had been partially sequenced for expressed sequence tags (5' EST) markers. Earlier database query via a BLAST program indicated that a partial DNA sequence from this clone matched enolase sequences from other eukaryotic organisms. DNA sequencing was thus performed on subcloned DNA fragments from PMM020 and an 1861 bp of combined sequence was found. A tract of poly (A) was found at the 3' side beyond position 1861 of the sequence, which indicated that the 3' end of the transcript was intact. An open reading frame for 434 amino acids was found starting from the predicted translation initiation codon (ATG) at nucleotide position 24 and ending at a termination codon (TAA) at position 1327. The predicted protein molecular weight was 47 kDa. An amino acid motif specific to enolase, DDLTVTNPK was found at residue positions 320 328. Upon comparing with an enolase cDNA sequence from Xenopus laevis, the overall nucleotide sequence identity between the two sequences was 62.0% while the identity within the open reading frame was 69.4% and the calculated protein sequence identity was 72.5%. When compared to those of other eukaryotes, the calculated amino acid sequence identities of 77.6% (Drosophila melanogaster), 63.1 % (yeast, Saccharomyces cerevisiae), 72.7% (chicken, Gallus gallus), 71.3% (mouse, Mus musculus) were found. The high percent identity for both nucleotide and predicted protein sequences, together with the expected length of the polypeptide chain, identified the cloned sequence as phosphopyruvate hydratase (GenBank accession no. AFI 00985)
Keywords: Prawn, phosphopyruvate hydratase, enolase, shrimp
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