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INHIBITORS OF HOST DEATH. "Numerous viruses indeed have evolved mechanisms preventing host cell death, often by recruiting genes involved in host suicide and turning them into competitive inhibitors of cell death or else via repair of the damage involved in cell death." Cunning strategy. https://lnkd.in/d9zsv9R View in LinkedIn

"REDUCED VIRULENCE is the most likely evolutionary outcome under conditions of low pathogen dispersal, whereas intermediate dispersal rates can lead to high virulence. It is therefore plausible that, in structured populations, the host-pathogen arms race has a major effect on the genes involved in cell death and its inhibition." https://lnkd.in/d9zsv9R View in LinkedIn

SUICIDE AVERSION. "It has been shown that experimental evolution of phages under conditions of local dispersion leads to ‘prudent’ (less virulent) variants of the virus, in contrast to the virulent forms evolved in a well-mixed environment." https://lnkd.in/d9zsv9R View in LinkedIn

NON-ALIGNED INTERESTS. "The results of the present model of suicide evolution reveal an antagonism between the ‘interests’ of hosts and pathogens in structured populations whereby, while hosts tend to evolve suicide, prevention of host death is the preferred strategy for the pathogen." https://lnkd.in/d9zsv9R View in LinkedIn

FINAL NOTE. "Perhaps somewhat paradoxically, fixation of a costly adaptive immunity system is precluded not only when the innate immunity and suicide systems are highly effective but also when adaptive immunity itself performs at a high level. In such a case, hosts with and without adaptive immunity coexist in an environment where the pathogen is scarce (herd immunity effect)." https://lnkd.in/d9zsv9R View in LinkedIn

SINGLE ENTITY. "Important to note is that in many cases the interests of the bacterium and an already resident prophage become completely aligned upon obligately lytic phage infection (i.e. infection by phages that do not insert into the bacterial genome, but kill the bacterium instantly), such that they can be regarded as one genetic entity." https://lnkd.in/d53-z28 View in LinkedIn

RULES FOR DEVELOPMENT. "Evolution of suicide as a defense mechanism is only possible if (i) the host population is structured and (ii) the degree of immunity that the hosts can achieve by other means is limited. The widespread nature of suicide systems in prokaryotic genomes calls for a reconsideration of the relative importance of population structure for genome evolution." https://lnkd.in/d9zsv9R View in LinkedIn

LEADING THE RACE. "Studies on host-parasite local adaptation suggest that parasites are usually ahead of hosts in this coevolutionary arms race." https://lnkd.in/d9zsv9R View in LinkedIn

SOCIAL POPULATIONS. "The presence of programmed cell death systems in the great majority of prokaryotes strongly suggests that structured populations are the rule in microbial ecosystems. Indeed, some kind of social interaction, such as biofilm formation, is found on almost every bacterial group, and more advanced forms of sociality, such as quorum sensing, are often present in Proteobacteria and Firmicutes." https://lnkd.in/d9zsv9R View in LinkedIn

CONSTRAINTS. "In real biological communities, the efficacy of innate and adaptive immune systems is constrained by ecological factors such as population size, structure and diversity. The never-stopping arms race between hosts and pathogens sets a limit on the performance of defense strategies, which is determined by the ability of the host to keep the pace with pathogen escape mutations." https://lnkd.in/d9zsv9R View in LinkedIn