Appl Microbiol Biotechnol
September 2015
Extein amino acid residues around the splice site junctions affect the functionality of inteins. To identify an optimal sequence context for efficient protein splicing of an intein from the thermoacidophilic archaeon Picrophilus torridus, single extein amino acid residues at the splice site junctions were continuously deleted. The construction of a set of different truncated extein variants showed that this intein tolerates multiple amino acid variations near the excision sites and exhibits full activity when -1 and +1 extein amino acid residues are conserved in an artificial GST-intein-HIS fusion construct.
View Article and Find Full Text PDFThe LE (LguI/Eco81I)-cloning procedure allows a step-wise, directional fusion of multiple DNA-fragments into a vector by utilizing two restriction enzymes generating identical non-palindromic overhangs. This strategy was applied to produce heat-stable cellulase-fusion proteins containing up to five single moieties. Terminal affinity tags enable efficient purification using a simple two-step approach.
View Article and Find Full Text PDFNAD(P)(+)-dependent alcohol dehydrogenases (ADH) are widely distributed in all phyla. These proteins can be assigned to three nonhomologous groups of isozymes, with group III being highly diverse with regards to catalytic activity and primary structure. Members of group III ADHs share a conserved stretch of amino acid residues important for cofactor binding and metal ion coordination, while sequence identities for complete proteins are highly diverse (<20 to >90 %).
View Article and Find Full Text PDFAlcohol dehydrogenases are highly diverse enzymes catalysing the interconversion of alcohols and aldehydes or ketones. Due to their versatile specificities, these biocatalysts are of great interest for industrial applications. The adh3-gene encoding a group III alcohol dehydrogenase was isolated from the gram-positive bacterium Oenococcus oeni and was characterised after expression in the heterologous host Escherichia coli.
View Article and Find Full Text PDFA pair of NAD(+)- and NADP(+)-dependent group III-alcohol dehydrogenases was characterized from the enterobacterium, Dickeya zeae, to expand our understanding of the distribution and biochemical properties of this interesting group of enzymes. Two putative group III-alcohol dehydrogenases (ADHs) were identified in the genome of Dickeya zeae. Amino acid alignments and phylogenetic analysis revealed that Adh3.
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