Background: Zymomonas mobilis , as a novel platform for bio-ethanol production, has been attracted more attention and it is very important to construct vectors for the efficient expression of foreign genes in this bacterium. Results: Three shuttle vectors (pSUZM1, pSUZM2 and pSUZM3) were first constructed with the origins of replication from the chromosome and two native plasmids (pZZM401 and pZZM402) of Z . mobilis ZM4, respectively. The three shuttle vectors were stable in Z . mobilis ZM4 and have 3, 32 and 27 copies, respectively. The promoter P pdc (a), from the pyruvate decarboxylase gene, was cloned into the shuttle vectors, generating the expression vectors pSUZM1(2, 3)a. The codon-optimized glucoamylase gene from Aspergillus awamori combined with the signal peptide sequence from the alkaline phosphatase gene of Z . mobilis was cloned into pSUZM1(2, 3)a, resulting in the plasmids pSUZM1a-GA, pSUZM2a-GA and pSUZM3a-GA, respectively. After transforming these plasmids into Z . mobilis ZM4, the host was endowed with glucoamylase activity for starch hydrolysis. Both pSUZM2a-GA and pSUZM3a-GA were more efficient at producing glucoamylase than pSUZM1a-GA. Conclusions: These results indicated that these expression vectors are useful tools for gene expression in Z . mobilis and this could provide a solid foundation for further studies of heterologous gene expression in Z . mobilis . 800x600 Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:Tabla normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Calibri,sans-serif;}