2.2 Plasmids, strains and medium
All strains and plasmids used in this study as shown in Table S1.The
sequence of SI gene from the Pantoea dispersa UQ68J (Pdsi )
(GenBank accession number:
AY223549)
without signal peptide was synthesized and sequenced by Suzhou GENEWIZ
Company, and 6xHistag was added to the C-terminal of Pdsi for the
protein purification. The Pdsigene was incorporated in between Hind III and EcoR I site of
the E. coli/C. glutamicum shuttle plasmid pXMJ19 to generate
pXMJ19-pdsi . E.coli strain JM109 was used as gene cloning
host to construct recombinant plasmids. C. glutamium 13032 was
used as expression host for the characterization of enzymatic properties
and whole cells were used as biocatalysts for isomaltulose production.E. coli cells were cultured at
37℃ in LB medium (NaCl 10 g/L, peptone 10 g/L, yeast extract 5 g/L).C. glutamium 13032 cells were grown on BHI medium at 30℃. 25
μg/mL chloramphenicol was added when necessary.