RICARDO GENARI CARACTERÍSTICAS DE ... - SBI-Café - UFV

characteristics of the pectinase produced were similar to those found in other
bacteria and fungi. The bacteria secreted pectate lyase when grown in medium
containing pectin of molecular mass greater than 30,000 Da, obtained by
ultrafiltration. The enzyme's secretion was inhibited by a compound present in the
pectin of molecular mass between 3,000 e 30,000 Da or by oligogalacturonides,
which could somehow be degraded by the bacteria. The substrate retained inside
2,000 and 14,000 Da dialysis membranes induced greater enzyme secretion, being
greatest in the 14,000 Da membranes. The compounds present in the Sigma citric
pectin that interfered in enzyme regulation mechanisms were not identified. K.
oxytoca quickly grewn when starch, galacturonate, poligalacturonate, casein, and
glucose were used as carbon source. However, growth was not observed when using
cellulose as carbon source. The depolymerizing enzymes were detected at minimal
levels, a characteristic of endophytic microorganisms. Endophytic bacteria, that
don’t make visible damage in the plants, should have some regulatory mechanism to
control the synthesis and the activity of their enzymes. The results indicate the
potential contribution of K. oxytoca in fermentative processes in coffee beans.
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