(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Fungi: NE > Dikarya: NE > Ascomycota: NE > saccharomyceta: NE > Saccharomycotina: NE > Saccharomycetes: NE > Saccharomycetales: NE > Trichomonascaceae: NE > Blastobotrys: NE > Blastobotrys adeninivorans: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MASIPFFVEMKHFLGQSLLTSLLAAGAFGSSLAEVCTSSRIRTALPKDGA IAGISMDPDSITANPVYNASAGYSVFYPEGNFDYCNVTVSYCHIGKGDKV NLQYWLPSPDKFQNRYLATGGGGYAINSGTQSLPGGVMYGAVAGRTDGGF GGFDVQVSEAILYANGSLNYDSLYMFGYRAIGEQTMIGQELARGFYELGD EKKIYTYYQGCSEGGREGWSQIQKFPDLYDGVIPAAPAFRYGHQQVNHLF PGVIEQGMNYYPPPCEMARIVNATIEACDKLDGKIDGVVSRTDLCLLNFD FNSTIGLHYTCEAGSNPMTGDSTPAQNGTVSTKAAELARVLTEGLHDSQG NKAYVFYQITAGYDDADTKYNPATGQFELSVSSLGGEWVTKLLQLVDLDN LPNLDNVTVDTLVDWMQCGWQTYEDVLQTTRPDLSLYERAGGKILTFHGE SDNSIPAGSSVHFYESVRNVMYPGISFNQSTDAMGEWYRLYLVPGAAHCS INALQPNGPFPQTTLEVMIDWVENGNTPTTLQATYLVGDNKGKPAEICPW PLRPTWTDEGSKLQCVYDHTSINTWMYDFNAFSLPVY
Tannase (tannin acyl hydrolase, EC 3.1.1.20) hydrolyses the ester and depside bonds of gallotannins and gallic acid esters and is an important industrial enzyme. In the present study, transgenic Arxula adeninivorans strains were optimised for tannase production. Various plasmids carrying one or two expression modules for constitutive expression of tannase were constructed. Transformant strains that overexpress the ATAN1 gene from the strong A. adeninivorans TEF1 promoter produce levels of up to 1,642 U L(-1) when grown in glucose medium in shake flasks. The effect of fed-batch fermentation on tannase productivity was then investigated in detail. Under these conditions, a transgenic strain containing one ATAN1 expression module produced 51,900 U of tannase activity per litre after 142 h of fermentation at a dry cell weight of 162 g L(-1). The highest yield obtained from a transgenic strain with two ATAN1 expression modules was 31,300 U after 232 h at a dry cell weight of 104 g L(-1). Interestingly, the maximum achieved yield coefficients [Y(P/X)] for the two strains were essentially identical.
Title: Atan1p-an extracellular tannase from the dimorphic yeast Arxula adeninivorans: molecular cloning of the ATAN1 gene and characterization of the recombinant enzyme Boer E, Bode R, Mock HP, Piontek M, Kunze G Ref: Yeast, 26:323, 2009 : PubMed
The tannase-encoding Arxula adeninivorans gene ATAN1 was isolated from genomic DNA by PCR, using as primers oligonucleotide sequences derived from peptides obtained after tryptic digestion of the purified tannase protein. The gene harbours an ORF of 1764 bp, encoding a 587-amino acid protein, preceded by an N-terminal secretion sequence comprising 28 residues. The deduced amino acid sequence was similar to those of tannases from Aspergillus oryzae (50% identity), A. niger (48%) and putative tannases from A. fumigatus (52%) and A. nidulans (50%). The sequence contains the consensus pentapeptide motif (-Gly-X-Ser-X-Gly-) which forms part of the catalytic centre of serine hydrolases. Expression of ATAN1 is regulated by the carbon source. Supplementation with tannic acid or gallic acid leads to induction of ATAN1, and accumulation of the native tannase enzyme in the medium. The enzymes recovered from both wild-type and recombinant strains were essentially indistinguishable. A molecular mass of approximately 320 kDa was determined, indicating that the native, glycosylated tannase consists of four identical subunits. The enzyme has a temperature optimum at 35-40 degrees C and a pH optimum at approximately 6.0. The enzyme is able to remove gallic acid from both condensed and hydrolysable tannins. The wild-type strain LS3 secreted amounts of tannase equivalent to 100 U/l under inducing conditions, while the transformant strain, which overexpresses the ATAN1 gene from the strong, constitutively active A. adeninivorans TEF1 promoter, produced levels of up to 400 U/l when grown in glucose medium in shake flasks.
