Open AccessCloning and targeted disruption of two polygalacturonase genes in Penicillium olsonii
Author(s) -
Wagner Florian,
Kusserow Heike,
Schäfer Wilhelm
Publication year - 2000
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2000.tb09120.x
Subject(s) - pectinase , biochemistry , gene isoform , arabinose , gene , biology , enzyme , cloning (programming) , penicillium , molecular cloning , chemistry , gene expression , genetics , fermentation , xylose , computer science , programming language
The filamentous fungus Penicillium olsonii secretes several polygalacturonases (PGs) with molecular masses of about 47 kDa. These enzymes consist of several basic and acidic isoforms, with dominant activities at p I 4.5 and p I 7.9. Two polygalacturonase genes, pg1 and pg2 , have been cloned. The corresponding enzymes, PG1 and PG2, consist of 370 and 380 amino acids, respectively, and show significant similarities to endo‐polygalacturonases from other filamentous fungi. Targeted disruption of pg1 resulted in the elimination of all basic PG isoforms. In contrast, disruption of pg2 reduced, but did not eliminate the acidic PG activities. The PGs of P. olsonii must therefore be encoded by a gene family of at least three genes. Induction studies with various carbon sources revealed that the acidic and basic isoforms are differentially regulated. Pectin is the best inducer of the acidic PG isoforms. The basic isoforms, however, are best induced by monosaccharides like glucose, α‐ L ‐rhamnose and α‐ L ‐arabinose.