Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evolutionary dynamics determines adaptation to inactivation of an
  essential gene   Genetic inactivation of essential genes creates an evolutionary scenario
distinct from escape from drug inhibition, but the mechanisms of microbe
adaptations in such cases remain unknown. Here we inactivate E. coli
dihydrofolate reductase (DHFR) by introducing D27G,N,F chromosomal mutations in
a key catalytic residue with subsequent adaptation by serial dilutions. The
partial reversal G27->C occurred in three evolutionary trajectories.
Conversely, in one trajectory for D27G and in all trajectories for D27F,N
strains adapted to grow at very low supplement folAmix concentrations but did
not escape entirely from supplement auxotrophy. Major global shifts in
metabolome and proteome occurred upon DHFR inactivation, which were partially
reversed in adapted strains. Loss of function mutations in two genes, thyA and
deoB, ensured adaptation to low folAmix by rerouting the
2-Deoxy-D-ribose-phosphate metabolism from glycolysis towards synthesis of
dTMP. Multiple evolutionary pathways of adaptation to low folAmix converge to
highly accessible yet suboptimal fitness peak.

17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin