反应详情

It was confirmed by 450 hours of cultivation in shake flasks on glucose that the hexokinase/glucokinase deletion strain IMK318 (hxk1Δ hxk2Δ glk1Δ) is unable to grow on glucose alone. Therefore the strain was cultivated in YP-EtOH/Glyc and subsequently stored at −80° C. after the addition of glycerol. Subsequently, IMK318 was cultivated in 100 ml MY containing 2% arabinose. After 3 days, at an OD660 of approximately 1, 2 ml of the culture was transferred to 100 ml fresh MY containing 2% arabinose. After approximately 12 days the OD660 of the culture was >5 and samples were stored at −80° C. as glycerol stocks. Strain IMK318 was cultivated at 30° C. for several days in MY-ara. At an OD660 of approximately 5, 2 ml of the culture was transferred to 6 separate shake flasks containing 100 ml MYurea supplemented with 2% arabinose and varying concentrations of glucose: 0, 0.11, 0.23, 0.65, 1.3 and 2.5 (w/v) %. Growth of these 6 parallel cultures was recorded by OD660 measurements (FIG. 3). It was observed that, in the presence of glucose, growth is delayed. An increasing amount of glucose resulted in an increasingly delayed growth on arabinose. Two of these parallel cultures (Line A which started at 0.65 w/v % glucose; Line B which started at 2.5 w/v % glucose) were transferred serially to 100 ml MY supplemented with arabinose and glucose according to the transfer-schemes shown in Table 4.

1. customsubsequently stored at −80° C.
2. waitAfter 3 days
3. waitAfter approximately 12 days the OD660 of the culture was
4. waitwas cultivated at 30° C. for several days in MY-ara
5. customseparate shake flasks
6. additioncontaining 100 ml MYurea