IDENTIFICATION OF GLUCURONAN LYASE FROM A MUTANT STRAIN OF RHIZOBIUM-MELILOTI

The Rhizobium meliloti M5N1CS (NCIMB 40472) mutant strain wich induces nodule formation on alfalfa roots, produces a (1 --> 4)-beta-D-glucur onan partially acetylated. During fermentation under specific conditio ns, the molecular weight of the polymer decrease, the presence of poly saccharide degrading enzyme was suspected. A glucuronan lyase was iden tified, this new bacterial lyase produces d.p. 4 oligoglucuronans, sub stituents (acetates) present on the substrate reduced the enzyme activ ity. (C) 1997 Elsevier Science B.V.