Abstract: Biotin (also called vitamin H or B7) is an important micronutrient that can participate in various metabolic processes as a cofactor for biotin-dependent enzymes (biotin-dependent carboxylase, decarboxylase, and transcarboxylase). When biotin is deficient, the vitality of the cells will be reduced, and even death will occur. The earliest discovered biotin metabolism regulator is BirA, which contains not only the DNA binding domain, but also the functional domain of protein biotin ligase.In recent years, it has been found that the biotin metabolism process in Prokaryotes presents a variety of regulatory modes. Currently, three types of regulatory factors, suchas BirA, BioR, and BioQ, have been identified, which respectively play a transcriptional regulatory role in the biotin metabolism genes of Prokaryotes such as γ-Proteobacterias, α-Proteobacterias and Actinomycetes. This review summarized these three types of regulatory factors, and focused on the research progress of their regulatory functions so as to provide a theoretical guidance for further revealing the molecular mechanisms of these regulatory factors.

Key words: Prokaryotes, biotin, metabolism regulation, regulatory factor