Purification and properties of a glucuronan lyase from Sinorhizobium meliloti M5N1CS (NCIMB 40472).
A glucuronan lyase extracted from Sinorhizobium meliloti strain M5N1CS was purified to homogeneity by anion-exchange chromatography. The purified enzyme corresponds to a monomer with a molecular mass of 20 kDa and a pI of 4.9. A specific activity was found only for polyglucuronates leading to the production of 4,5-unsaturated oligoglucuronates. The enzyme activity was optimal at pH 6.5 and 50 degrees C. Zn(2+), Cu(2+), and Hg(2+) (1 mM) inhibited the enzyme activity. No homology of the enzyme N-terminal amino acid sequence was found with any of the previously published protein sequences. This enzyme purified from S. meliloti strain M5N1CS corresponding to a new lyase was classified as an endopolyglucuronate lyase.
Da Costa
A
A
Laboratoire des Polysaccharides Microbiens et Végétaux, IUT, Département de Génie Biologique, Université de Picardie Jules Verne, Avenue des Facultés, Le Bailly, 80025 Amiens Cedex, France.
Michaud
P
P
Petit
E
E
Heyraud
A
A
Colin-Morel
P
P
Courtois
B
B
Courtois
J
J
D000595:Amino Acid Sequence; D008969:Molecular Sequence Data; D011133:Polysaccharide-Lyases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D016962:Sinorhizobium meliloti / Q000201:enzymology* / Q000254:growth & development; D013379:Substrate Specificity
D011133:Polysaccharide-Lyases; C109209:glucuronan lyase