pWB705 andpWB980 . pUB110 is the parental plasmid for pUB18 and its derivatives.pWB705  is a pUB18-based secretion vector carrying both the constitutive expressed P43 promoter and the engineered levansucrase signal sequence. pWB980 is a pUB19-based secretion vector. The transcription direction of the P43 promoter is the same as that for the majority of the pUB110-encoded genes. rep, kan, ble, mob and sacB SP represent thesequence coding for replicase, kanamycin resistance marker,bleomycin resistance marker, mobilization protein and the levansucrase signal sequence, respectively. The arrows show the transcription directions for these genes.