Fig. 2
Determination of the minimal stnYp promoter. The schematic diagram of the reporter constructs harboring the full-length promoter stnYp339 and truncated mutants. Here, the marked 289 bp, 150 bp, 100 bp, 80 bp, 60 bp, 30 bp and 10 bp represented the upstream DNA length of the − 35 region (TTGGCG), corresponding to stnYp339, stnYpup150, stnYpup100, stnYpup80, stnYpup60, stnYpup30 and stnYpup10, respectively. The activities of truncated promoters were evaluated using xylE as a reporter gene in S. albus J1074. XylE assay was carried out with samples harvested after 24 h culture. Statistical analyses were performed and marked (***, p ≤ 0.01)