Cloning and nucleotide sequence of a gene encoding a glycogen debranching enzyme in the trehalose operon from Arthrobacter sp Q36

A gene located just upstream of the tre YZ operon was isolated from Arthrobacter sp. strain Q36. The gene, designated treX, encoded an 823-amino acid protein. The amino acid sequence of the protein had 50% identity with the TreX protein (isoamylase) from Sulfolobus acidocaldarius ATCC 33909 which has a treZXY operon on the genome. We suggest that Arthrobacter treX is an isoamylase gene, and that it is a component of a treXYZ operon. (C) 2000 Elsevier Science B.V. All rights reserved.