CAJ | 학술논문

从前期得到的一株能在厌氧下高效利用甘油的大肠杆菌突变株 HW2出发，通过基因工程改造，提高菌株利用甘油产氢气的能力。首先敲除乳酸脱氢酶基因ldhA和丙酮醛合成酶基因mgsA，得到工程菌株HW2ΔldhAΔmgsA。将该菌株在甘油培养基中厌氧培养，结果表明敲除这两基因不影响菌株的生长。培养48 h后，菌株HW2ΔldhAΔmgsA的氢气产量为(410.6±33.0)μmol×mg protein-1，是出发菌株HW2的1.6倍。接着在该菌株中过表达经密码子优化的弗氏柠檬杆菌二羟基丙酮激酶来进一步提高氢气的产量。最终获得氢气高产菌株HW2ΔldhAΔmgsA pCA24N-dhaKL，经过厌氧培养48h后，氢气产量为(571.5±30.3)μmol×mg protein-1，是出发菌株HW2的2.1倍。
종전기득도적일주능재염양하고효이용감유적대장간균돌변주 HW2출발，통과기인공정개조，제고균주이용감유산경기적능력。수선고제유산탈경매기인ldhA화병동철합성매기인mgsA，득도공정균주HW2ΔldhAΔmgsA。장해균주재감유배양기중염양배양，결과표명고제저량기인불영향균주적생장。배양48 h후，균주HW2ΔldhAΔmgsA적경기산량위(410.6±33.0)μmol×mg protein-1，시출발균주HW2적1.6배。접착재해균주중과표체경밀마자우화적불씨저몽간균이간기병동격매래진일보제고경기적산량。최종획득경기고산균주HW2ΔldhAΔmgsA pCA24N-dhaKL，경과염양배양48h후，경기산량위(571.5±30.3)μmol×mg protein-1，시출발균주HW2적2.1배。
An engineeredE. colistrain was constructedto enhancethehydrogen productionofEscherichia coliHW2 that can dissimilate glycerol effectivelyunderanaerobic condition.TheldhAandmgsAgeneswere first knocked outto constructHW2ΔldhAΔmgsA. This new straingrewsimilarly asHW2 in glycerol medium and produced(410.6±33.0)μmol×mg protein-1of hydrogen in 48 h, which was 1.6-foldhigher thanthat of HW2. ThedhaKLgenecoded dihydroxyacetone kinasefromCitrobacter freundiiwas optimized and overexpressedin HW2ΔldhAΔmgsA.The strainHW2ΔldhAΔmgsApCA24N-dhaKLcanproduce(571.5±30.3)μmol×mg protein-1of hydrogen in 48 h, whichis2.1-fold higher than that ofthe original strain HW2.