Zymomonas is an efficient ethanol producer, together with a higher tolerance to ethanol and to several inhibitory substances of lignin. Zymomonas species also possess a gene that codes for cellulase (Rajnish et al. 2008). While protein secretion is not a hurdle in Zymomonas spp., a major difficulty arises with the lack of amenable genetic tools for the introduction or modification of a gene (Linger et al. 2010). Two cellulases from Acidothermus cellulolyticus have been expressed in Z. mobilis, and a significant amount of secretion was observed when they were fused with predicted N-terminal signal peptides of Z. mobilis (Linger et al. 2010). Endoglucanases from different cellulolytic organisms such as Cellulomonas spp., Enterobacter cloacae, Pseudomonas fluorescens, and Erwinia spp., have been expressed in Z. mobilis. However, none of these cellulases were secreted efficiently (Lejeune et al. 1988; Misawa et al. 1988; Brestic-Goachet et al. 1989; Thirumalai Vasan et al. 2011).