Programmable domestication of thermophilic bacteria through removal of non-canonical defense systems

Abstract Thermophilic bacteria offer major advantages for industrial biotechnology, yet most remain genetically intractable because cellular defense systems block efficient DNA acquisition. Here, we present a programmable domestication strategy that converts wild Geobacillus strains into genetically tractable thermophilic hosts. We developed the Domestication of Non-Model Bacteria (DNMB) Suite, a multi- omics-guided computational framework that systematically identifies genetic barriers to transformation. DNMB analysis revealed that non-canonical nuclease-based defense systems, including Wadjet II, constitute dominant barriers to DNA uptake in previously intractable Geobacillus strains. Targeted deletion of these loci increased transformation efficiency by up to six orders of magnitude. We further established a hierarchical thermophilic engineering toolkit that integrates plasmid artificial modification, conjugation-assisted DNA delivery, and genome editing using an endogenous CRISPR-Cas9 system. The resulting domesticated strains support stable heterologous expression and tunable genetic control at elevated temperatures. Together, these results establish a generalizable framework for transforming genetically intractable thermophiles into programmable industrial chassis.