Objective Identification and characterization of a novel bacterial carbohydrate esterase (PaCes7) with application potential for lignocellulose and pesticide degradation. Results PaCes7 was identified from the lignocellulolytic bacterium,Pantoea ananatisSd-1 as a new carbohydrate esterase. Recombinant PaCes7 heterologously expressed inEscherichia colishowed a clear preference for esters with short-chain fatty acids and exhibited maximum activity towards alpha-naphthol acetate at 37 degrees C and pH 7.5. Purified PaCes7 exhibited its catalytic activity under mesophilic conditions and retained more than 40% activity below 30 degrees C. It displayed a relatively wide pH stability from pH 6-11. Furthermore, the enzyme was strongly resistant to Mg2+, Pb2+, and Co(2+)and activated by K(+)and Ca2+. BothP. ananatisSd-1 and PaCes7 could degrade the pesticide carbaryl. Additionally, PaCes7 was shown to work in combination with cellulase and/or xylanase in rice straw degradation. Conclusions The data suggest that PaCes7 possesses promising biotechnological potential.