11 September 2005
FEBS-let: Functional essentiality from topology features in metabolic
Interesting in relation to ongoing work on essentiality and lethality.
FEBS Lett. 2005 Aug 29;579(21):4642-4646.
Functional essentiality from topology features in metabolic networks: A
case study in yeast.
Palumbo MC, Colosimo A, Giuliani A, Farina L.
The relation between the position of mutations in Saccharomyces cerevisiae
metabolic network and their lethality is the subject of this work. We represent
the topology of the network by a directed graph: nodes are metabolites and arcs
represent the reactions; a mutation corresponds to the removal of all the arcs
referring to the deleted enzyme. Using publicly available knock-out data, we
show that lethality corresponds to the lack of alternative paths in the
perturbed network linking the nodes affected by the enzyme deletion. Such
feature is at the basis of the recently recognized importance of 'marginal' arcs
of metabolic networks.