Borrellia.afzelii phosphatidylcholine synthase gene（pcs） was introduced into a phosphatidylethanolamine（PE） negative strain AD93 to create strain E.coli AD93/ptac67（PC+PE-）.Physiological and biochemical characteristics were preliminarily investigated and compared among the strain AD93/ptac67 and two control strains AD93 and AD93/pDD72.Our results showed（1） the growth of AD93/ptac67 required more than 10 mmol/L Mg2+

2-fold less than that（20 mmol/L） for AD93

however AD93/pDD72 didn’t need any extra Mg2+ for its growth;（2） Like AD93

AD93/ptac67 was sensitive to the detergent SDS with a value of minimal inhibition concentration（MIC） of 0.02%

10-fold less than that for AD93/pDD72;（3） 5% NaCl completely inhibited the growth of AD93/ptac67

3% NaCl almost inhibited the growth of AD93 strain

but AD93/pDD72 strain was able to grow even if NaCl concentration was up to 5%.Three strains showed different patterns of periplasmic proteins on SDS-PAGE gel.Our results demonstrated that the incorporation of PC into the membrane lacking PE was unable to fully restore the function of PE-negative cells.