Probable S-adenosyl-L-methionine-dependent methyltransferase. Plays a role in both resistance to oxidative damage and heme uptake/utilization, and is important for virulence of this organism in an animal model of invasive disease. Also protects H.influenzae from tellurite exposure in vitro; however, since H.influenzae grows only in humans, it is unlikely to encounter tellurite in its natural environment, and it is thus probable that tellurite resistance does not represent a biologically relevant role of TehB. Transcription of tehB is independent of both tellurite exposure and oxidative stress. Deletion of tehB leads to an increase in sensitivity both to tellurite and to the oxidizing agents cumene hydroperoxide, tert-butyl hydroperoxide and hydrogen peroxide. The tehB mutant additionally shows a significantly reduced ability to utilize free heme as well as several heme-containing moieties including heme-human serum albumin, hemoglobin and hemoglobin-haptoglobin, to support aerobic growth. Virulence of the mutant strain is reduced compared to the wild-type strain in the infant rat. Belongs to the TehB family.