Production of Vitamin E in Erwinia herbicola Bearing the Vitreoscilla Hemoglobin Gene (vgb+)

Vitreoscilla hemoglobin (VHb) is bacterial hemoglobin and has beneficial effects on heterologous organisms. The VHb/vgb system, in the advanced phases of the culture, transfers oxygen to the membrane transferases, giving the elderly cells the ability to better oxygen-uptake, grow and proliferate. In this study was investigated the intracellular and extracellular production of vitamin E in Erwinia herbicola and its recombinant strains (vgb- and vgb+). There was a significant increase the production of vitamin E in the vgb+ strain in the LB medium. Production of total vitamin E in the vgb+ recombinant strain had 2-fold higher than its host. The wild strain produced 0.06 μg/mL total vitamin E, whereas the recombinant bacteria carrying the vgb gene produced 0.12 μg/mL the product. In addition, production of vitamin E was investigated in the minimal medium (M9) including 1% concentrations of different carbon resources such as glucose, sucrose and fructose. It was recorded that the vitamin E levels produced by the recombinant strain in the culture containing 1% fructose were higher than with 1% glucose and sucrose cultures. The findings showed that the presence of vgb may provide an effective biotechnological method to increase yield of vitamin E.