Table 1. Mutagenesis and selection of mutants.

Mutagenesis conditions

Colonies

Transfers

Stability

Concentration of MNNG*, μg/ml

Exposure time, min

100

(OD=1.2)

20

3

 

2

 

-

30

none

40

none

75

(OD=1.2)

 

30

 

11

 

3

 

-

50

(OD=0.684)

 

30

 

19

 

6

 

+

50

(OD=0.81)

 

30

 

14

 

6

 

+

50

(OD=1.24)

 

30

 

3

 

6

 

+

MNNG:N-methyl, N'-nitro, N-nitrosoguanidine
- stable
+ unstable
OD: Cell Optical Density at 600 nm


Supported by UNESCO / MIRCEN network