biostudies-literatureZhou CNational Natural Science Foundation of Chinathe 863 Plan of ChinaNatural Science Foundation of Jiangsu Province111https://www.ebi.ac.uk/biostudies/studies/S-EPMC6570832biostudies-literatureUnknown18(1)<h4>Background</h4>Bacillus subtilis is developed to be an attractive expression host to produce both secreted and cytoplasmic proteins owing to its prominent biological characteristics. Chromosomal integration is a stable expression strategy while the expression level is not ideal compared with plasmid expression. Thus, to meet the requirement of protein overexpression, promoter, as one of the key elements, is important. It is necessary to obtain an ideal promoter for overproduction of foreign proteins from a single copy expression cassette.<h4>Results</h4>The activity of promoter P_ylb was further enhanced by optimizing the - 35, - 10 core region and upstream sequence (UP) by substituting both sequences with consensus sequences. The final engineered promoter exhibited almost 26Microbial cell factoriesPromoter engineering enables overproduction of foreign proteins from a single copy expression cassette in Bacillus subtilis.PMC65708323180009531770125BK201805412014AA020543Cheng SLiu YJiang JZhao LZhou CYe BYan XfalsePromoter engineering enables overproduction of foreign proteins from a single copy expression cassette in Bacillus subtilis.<h4>Background</h4>Bacillus subtilis is developed to be an attractive expression host to produce both secreted and cytoplasmic proteins owing to its prominent biological characteristics. Chromosomal integration is a stable expression strategy while the expression level is not ideal compared with plasmid expression. Thus, to meet the requirement of protein overexpression, promoter, as one of the key elements, is important. It is necessary to obtain an ideal promoter for overproduction of foreign proteins from a single copy expression cassette.<h4>Results</h4>The activity of promoter P_ylb was further enhanced by optimizing the - 35, - 10 core region and upstream sequence (UP) by substituting both sequences with consensus sequences. The final engineered promoter exhibited almost 262019-01-01T00:00:00Z2019 Jun2025-04-26T02:13:56.197Z2019-07-24T07:18:53ZS-EPMC65708323120072210.1186/s12934-019-1159-0