1887

Abstract

A gene encoding the periplasmic α-amylase of K-11151 was cloned into using pUC19 as a vector. An ORF of 1578 bp was deduced to be the amylase structural gene. The primary structure of the enzyme had little identity with other α-amylases, except with the enzyme from The enzyme was expressed in from the promoter of pUC19 and was found to be transported to the periplasmic space. The expressed enzyme showed the same thermal stability, optimum temperature and substrate specificity as the enzyme from The enzyme formed maltotetraose, but not 6- nor 6-maltosyl-maltose, from maltose by the reverse reaction, and the tetraose was then hydrolysed to maltotriose and glucose. The addition of maltotriose enhanced the production of glucose from maltose. In addition, maltose was formed by the condensation of glucose by the enzyme. Thus, the periplasmic α-amylase of was shown to produce glucose from maltose by hydrolysing maltotetraose and possibly higher maltooligosaccharides, which were the products of a condensation reaction, as a major pathway, and by direct hydrolysis of maltose as a minor pathway.

Loading

Article metrics loading...

/content/journal/micro/10.1099/13500872-142-6-1505
1996-06-01
2020-01-24
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/journal/micro/10.1099/13500872-142-6-1505
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error