PMC:2726282 / 1662-2126 JSONTXT

{"project":"2_test","denotations":[{"id":"18599074-16311037-62517910","span":{"begin":253,"end":254},"obj":"16311037"},{"id":"18599074-15680762-62517911","span":{"begin":463,"end":464},"obj":"15680762"}],"text":"In bacteria, coupling of gene expression with external conditions is achieved through two molecular functions: (i) binding of transcription factors (TFs) at specific sites in the genome and (ii) recognition of a relevant effector signal or metabolite.1,2 Typically, these functions are performed by different domains of a single polypeptide, but there are also cases where two interacting proteins are responsible for these functions, as in two-component systems.3"}