Mobilization of selenium by a selenium-dependent bacterium.
A selenium-dependent bacterium, Bacillus sp., failed to grow on selenium-free media. However, it is able to grow at high concentrations of sodium selenite containing media up to 3% (w/v). It accumulated extraordinary high quantities of selenium, 432 ppm/mL. The bacterium generated the transformation of inorganic selenium into volatile selenium form(s) into the atmosphere. The biological release of volatile selenium basically depended on several factors: incubation temperature, pH, incubation periods, and substrate concentration. Maximal quantity of the volatile selenium form was obtained at 30 degrees C, pH 7, and 1% (w/v) sodium selenite.
Department of Botany, Faculty of Science, Al-Azhar University, Medinet Nasr, Cairo, Egypt.
A A
AA
Razak
S E
SE
Ramadan
K
K
el-Zawahry
D001407:Bacillus / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D012643:Selenium / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors; D014835:Volatilization
D012643:Selenium