Characterization of pectin lyase produced by an endophytic strain isolatedfrom coffee cherries

Aims: The effect of endophytic bacterial activity on the quality of coffee beverage was studied. Methods and Results: A survey of the micro-organisms in coffee cherries was performed before harvesting, and their growth on the main nutrients availa ble in coffee cherries was determined in vitro. Conclusions: Many endophytic bacteria were isolated from surface-sterilized coffee cherries. One of the pectinolytic strains was physiologically and p henotypically characterized, and was tentatively identified by partial 16S rDNA sequencing as Paenibacillus amylolyticus. This endophytic strain produ ced an extracellular pectinase with maximal activity at 40 degreesC and pH 7.9, and was thermostable up to 45 degreesC. EDTA and metal ions had little effect on pectin lyase activity. K-m and V-max values were 4.6 mg ml(-1) a nd 94.0 10(-8) mol min(-1) ml(-1), respectively. Significance and Impact of the Study: Pectin lyases have been found in fung i but rarely in bacteria, and this isolate is a promising tool for regulati on studies of these enzymes.