Fig. 3

Expression and depolymerase activity of recombinant K57-Dpo8. A Purified K57-Dpo8 was separated by 10% sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and stained with Coomassie blue. B Polysaccharide-degrading activity of K57-Dpo8 was assessed using a modified single-spot assay on a lawn of K. pneumoniae strain 8665, with K57-Dpo8 dilutions ranging from 0.75 mg/mL to 75 ng/mL; K64-ORF41 (0.75 mg/mL) served as a negative control. C Size-exclusion chromatography-high performance liquid chromatography (SEC-HPLC) analysis of CPS samples treated with K57-Dpo8. The red line represents purified, untreated K57 CPS; the green line indicates K57-Dpo8 alone; the blue line shows K57 CPS incubated with 0.75 mg/mL K57-Dpo8 at 37 °C for 30 min; the gray line represents K57 CPS treated with 0.75 mg/mL K64-ORF41 at 37 °C for 30 min