Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lethality and synthetic lethality in the genome-wide metabolic network
  of Escherichia coli   Recent genomic analyses on the cellular metabolic network show that reaction
flux across enzymes are diverse and exhibit power-law behavior in its
distribution. While one may guess that the reactions with larger fluxes are
more likely to be lethal under the blockade of its catalyzing gene products or
gene knockouts, we find, by in silico flux analysis, that the lethality rarely
has correlations with the flux level owing to the widespread backup pathways
innate in the genome-wide metabolism of \textit{Escherichia coli}. Lethal
reactions, of which the deletion generates cascading failure of following
reactions up to the biomass reaction, are identified in terms of the Boolean
network scheme as well as the flux balance analysis. The avalanche size of a
reaction, defined as the number of subsequently blocked reactions after its
removal, turns out to be a useful measure of lethality. As a means to elucidate
phenotypic robustness to a single deletion, we investigate synthetic lethality
in reaction level, where simultaneous deletion of a pair of nonlethal reactions
leads to the failure of the biomass reaction. Synthetic lethals identified via
flux balance and Boolean scheme are consistently shown to act in parallel
pathways, working in such a way that the backup machinery is compromised.

20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int