Transcriptional Regulatory Network Differences between Six Industrial Escherichia coli Strains

Escherichia coli strains are widely used across numerous industrial and biotechnological applications. Yet their performance varies substantially in ways that can not be anticipated from genome annotation. Because transcriptional regulatory networks (TRNs) govern cellular functions such as motility, stress responses, metabolic flexibility, and production efficiency, differences in TRN organization and use may underlie many observed phenotypic differences. To investigate TRN differences between strains, we generated a compendium of 433 matched RNA-Seq profiles for six commonly used industrial E. coli strains (BL21, C, Crooks, MG1655, W, and W3110) and applied iModulon analysis to compare the state of their TRNs under similar growth conditions. This analysis revealed that core regulatory programs with similar functions are wired differently across the strains, and that the strains engage these programs in distinct ways when exposed to the same environmental challenges. Together, these findings highlight transcriptional regulation diversity underlying phenotypic expression among industrial E. coli strains. By providing an integrated view of TRN differences across widely used hosts, this work offers a fundamental basis for interpreting strain-specific behaviors and supports more informed approaches to strain selection and optimization.