Fig. 4

Secretory protein production by the tubB-deficient strains and parent strain PC-3-7. a Time course of the amount of secretory protein. Fermentation was conducted using 10% (w/v) microcrystalline cellulose and 2% (w/v) beechwood xylan as carbon sources. Data are expressed as mean ± SD of three biological replicates. b Amount of secreted protein at the end of cultivation. Data are expressed as mean ± SD of three biological replicates. Statistical significance was determined by two-tailed unpaired Student’s t-test. *p < 0.05