Editors' ChoiceMicrobiology

Globin-Coupled Sensors

Science's STKE  07 Aug 2001:
Vol. 2001, Issue 94, pp. tw12
DOI: 10.1126/stke.2001.94.tw12

Certain bacteria sense and exhibit an aerotactic response to oxygen. Hou et al. have identified a domain structurally related to myoglobin in aerotactic signal transducers HemAT from Halobacterium salinarum and Bacillus subtilis that bind heme and reversibly bind oxygen. Site-directed mutagenesis studies confirming the presence of a conserved histidine critical for heme binding and aerotactic responses support the structural modeling of these protein domains on myoglobin. Searches of genetic databases identified six HemAT homologs, two of which were analyzed to confirm their oxygen binding. Hou et al. call these proteins globin-coupled sensors, because each of the HemAT homologs appears to have the oxygen-sensing domain and a variable signal transducing domain.

S. Hou, T. Freitas, R. W. Larsen, M. Piatibratov, V. Sivozhelezov, A. Yamamoto, E. A. Meleshkevitch, M. Zimmer, G. W. Ordal, M. Alam, Globin-coupled sensors: A class of heme-containing sensors in Archaea and Bacteria. Proc. Natl. Acad. Sci. U.S.A. 98, 9353-9358 (2001). [Abstract] [Full Text]