The culture of Magnetospirillum magneticum WM-1 depends on several control factors that have great effect on the magnetic cells concentration. Investigation into the optimal culture conditions needs a large number of ...The culture of Magnetospirillum magneticum WM-1 depends on several control factors that have great effect on the magnetic cells concentration. Investigation into the optimal culture conditions needs a large number of experiments So it is desirable to minimize the number of experiments and maximize the information gained from them. The orthogonal design of experiments and mathematical statistical method are considered as effective methods to optimize the culture condition of magnetotactic bacteria WMol for high magnetic cells concentration. The effects of the four factors, such as pH value of medium, oxygen concentration of gas phase in the serum bottle, C:C (mtartaric acid: m=succinic acid) ratio and NaNO3 concentration, are simultaneously investigated by only sixteen experiments through the orthogonal design L16(44) method. The optimal culture condition is obtained. At the optimal culture condition ( pH 7.0, an oxygen concentration 4.0%, C:C (mtartaric acid: m=succinic acid) ratio 1:2 and NaNO3 100 mg 1^-1), the magnetic cells concentration is promoted tO 6.5×10^7 cells ml^-1, approximately 8.3% higher than that under the initial conditions. The pH value of medium is a very important factor for magnetic cells concentration. It can be Proved that the orthogonal design of experiment is of 90% confidence. Ferric iron uptake follows MichaelisoMenten kinetics with a Km of 2.5 pM and a Vmax of 0.83 min^-1.展开更多
文摘The culture of Magnetospirillum magneticum WM-1 depends on several control factors that have great effect on the magnetic cells concentration. Investigation into the optimal culture conditions needs a large number of experiments So it is desirable to minimize the number of experiments and maximize the information gained from them. The orthogonal design of experiments and mathematical statistical method are considered as effective methods to optimize the culture condition of magnetotactic bacteria WMol for high magnetic cells concentration. The effects of the four factors, such as pH value of medium, oxygen concentration of gas phase in the serum bottle, C:C (mtartaric acid: m=succinic acid) ratio and NaNO3 concentration, are simultaneously investigated by only sixteen experiments through the orthogonal design L16(44) method. The optimal culture condition is obtained. At the optimal culture condition ( pH 7.0, an oxygen concentration 4.0%, C:C (mtartaric acid: m=succinic acid) ratio 1:2 and NaNO3 100 mg 1^-1), the magnetic cells concentration is promoted tO 6.5×10^7 cells ml^-1, approximately 8.3% higher than that under the initial conditions. The pH value of medium is a very important factor for magnetic cells concentration. It can be Proved that the orthogonal design of experiment is of 90% confidence. Ferric iron uptake follows MichaelisoMenten kinetics with a Km of 2.5 pM and a Vmax of 0.83 min^-1.