Biochemical and molecular characterization of a novel glycerol dehydratase from Klebsiella pneumoniae 2e with high tolerance against crude glycerol impurities.

Background: The direct bioconversion of crude glycerol, a byproduct of biodiesel production, into 1,3-propanediol by microbial fermentation constitutes a remarkably promising value-added applications. However, the low activity of glycerol dehydratase, which is the key and rate-limiting enzyme in the 1,3-propanediol synthetic pathway, caused by crude glycerol impurities is one of the main factors affecting the 1,3-propanediol yield. Hence, the exploration of glycerol dehydratase resources suitable for crude glycerol bioconversion is required for the development of 1,3-propanediol-producing engineered strains.

Integrin αvβ6 sustains and promotes tumor invasive growth in colon cancer progression.

Aim: To detect the mechanism by which colon tumor escapes the growth constraints imposed on normal cells by cell crowding and dense pericellular matrices.

Methods: An immunohistochemical study of integrin αvβ6 and matrix metalloproteinase-9 (MMP-9) was performed on tissue microarrays of 200 spots, including 100 cases of colon tumors.

Results: High immunoreactivity for αvβ6 (73.