nonreplicating state is imposed [5]. However, others, such as oxyphenbutazone, depend on one or more of the conditions for their
activity [9, 49–51]. To identify which component of the multistress
model is important for a compound’s activity requires testing the
conditions in all combinations, which requires 2
N tests for
N conditions (Table 2). Second, exposure to reactive nitrogen
intermediates alone induces a transcriptional response in
M. tuberculosis that encompasses the smaller sets of responses
induced by most of the other conditions, including
M. tuberculosis’s transcriptional response to residence in an activated macrophage [52].
Below, we present a detailed description of the multistress
model of nonreplication in 96-well and 384-well formats. HTS
conducted with this assay against over 1,000,000 compounds
from academic and pharmaceutical libraries has identified hundreds
of compounds with selective bactericidal activity against both nonreplicating M. tuberculosis or with activities against replicating and
nonreplicating M. tuberculosis [9, 10, 49–51, 53].
Table 2
Description of different media used to identify which condition, or combination of conditions, is
responsible for a nonreplicating-active small molecule to kill M. tuberculosis in the multistress model
of nonreplication
Deconvolution medium
pH
Butyrate
Nitrite
Oxygen (%)
a
5.0
Yes
Yes
1
b
5.0
Yes
No
1
c
5.0
No
Yes
1
d
5.0
No
No
1
e
7.0
Yes
Yes
1
f
7.0
Yes
No
1
g
7.0
No
Yes
1
h
7.0
No
No
1
a
5.0
Yes
Yes
20
b
5.0
Yes
No
20
c
5.0
No
Yes
20
d
5.0
No
No
20
e
7.0
Yes
Yes
20
f
7.0
Yes
No
20
g
7.0
No
Yes
20
h
7.0
No
No
20
Alternatively, a compound may kill nonreplicating M. tuberculosis regardless of the media conditions. A total of 16 tests
(2
N for N tests; thus, 2
4
) are required to deconvolute four media conditions
616
Ben Gold et al.
activity [9, 49–51]. To identify which component of the multistress
model is important for a compound’s activity requires testing the
conditions in all combinations, which requires 2
N tests for
N conditions (Table 2). Second, exposure to reactive nitrogen
intermediates alone induces a transcriptional response in
M. tuberculosis that encompasses the smaller sets of responses
induced by most of the other conditions, including
M. tuberculosis’s transcriptional response to residence in an activated macrophage [52].
Below, we present a detailed description of the multistress
model of nonreplication in 96-well and 384-well formats. HTS
conducted with this assay against over 1,000,000 compounds
from academic and pharmaceutical libraries has identified hundreds
of compounds with selective bactericidal activity against both nonreplicating M. tuberculosis or with activities against replicating and
nonreplicating M. tuberculosis [9, 10, 49–51, 53].
Table 2
Description of different media used to identify which condition, or combination of conditions, is
responsible for a nonreplicating-active small molecule to kill M. tuberculosis in the multistress model
of nonreplication
Deconvolution medium
pH
Butyrate
Nitrite
Oxygen (%)
a
5.0
Yes
Yes
1
b
5.0
Yes
No
1
c
5.0
No
Yes
1
d
5.0
No
No
1
e
7.0
Yes
Yes
1
f
7.0
Yes
No
1
g
7.0
No
Yes
1
h
7.0
No
No
1
a
5.0
Yes
Yes
20
b
5.0
Yes
No
20
c
5.0
No
Yes
20
d
5.0
No
No
20
e
7.0
Yes
Yes
20
f
7.0
Yes
No
20
g
7.0
No
Yes
20
h
7.0
No
No
20
Alternatively, a compound may kill nonreplicating M. tuberculosis regardless of the media conditions. A total of 16 tests
(2
N for N tests; thus, 2
4
) are required to deconvolute four media conditions
616
Ben Gold et al.