Evolutionary Directed Computation
Based on DNA Mismatch Repair Systems
(darko.roglic@hau.hr)
The most important thing for
science is searching for truth. Through numerous discipline scientists reach
the point where they need more powerfull techniques and tools for their tasks.
Without new tools some of truths are still uncatchable and they will stay where
they are - in the unknown space - usually refered as complexity. Complexity
theory can be defined as the search for algorithms used in nature that display
common features across many levels of organization. In evolution directed
methods a key challenge is that only the small fraction of diversity can be
characterized regardless of the efficiency of the screening procedure used. For
example, a 500-bp gene implies alternatives, but
even the most efficient methods are restricted to alternatives.
Materials and methods:This paper has focus on
evolution because it already give us the notion of basic principles for
increasing complexity and efficiency. Because evolutionary research moved from
dinosaur fossils to microorganisms and genes that are evolving much faster, we
can get an insights into new paradigms of evolutionary adaptibility, also
called evolvability. New emerging science is experimental evolution which
allows to see little deeper than Darwin could at his time. Recent scientists
success has indentified that several enzymes were clearly designed to produce
mutations (DNA mutases). This was the ultimate validation of thirty years old
Radman’s iconoclastic hypothesis of process called SOS-induced error-prone
repair. This also has changed the notion of nature’s perfection and the dogma
that mutation is merely an unavoidable stochastic event due to the limits of
the precision of biological processes. What we have now is that genomic
mutations are genetically well controled processes and indentifed enzymes
become agents by which evolution can evolve rather than be the passive
supstrates of evolution. This new insights in evolutionary concepts (rather
then laws) and data, that we can get from experimental evolution, could be make
a starting point to transfere analog world of evolution into the digital one.
Main purpose will be: to use the concept of self-evolvability to create
solutions (by targeted and/or untargeted mutations and recombinations) in
reasonable time (and cost) through numerous alternatives when the arrival
problem (selective pressure) has never been seen before. Through evolution
bacterial populations developed such strategies toward perfection. Its
succesfull adaptibility, even in the extremely
difficult conditions for survival, relies mostly on homeologes recombinations
that allow the exchange of the genetic informations between different species.
This work explaines agents of
evolvability as extracted data and concepts from experimental evolution and
suggests evolutionary directed computation (EDC-model) based on them.
Results:Recently, few remarkable stories of
superrecursive algorithms have been reported. New theory suggested as first:
SR-algorithms could produce their result without stopping (e.g.sITM); and
second: SR-paradigm allows computation that changes computational procedure. It
seems that evolution implicates what superrecursive theory postulates. In the
first case, superrecursivity (through EDC-model) could be supported by
hypermutable genes (level of particular sequences) and/or by genetic mutators
(level of bacterial populations). We can also take into consideration permanent
production of antibodies of immune system that constatly improve the solutions,
and brain/mind communication system (through Soucek’s model called
Quantum-Mind) with its continuos quantizing discrete (CQD) processes of information
(from micro to macro level of higher organisms: firefly, katydid, birds, and
human).
Second feature of
superrecursivity could be supported by mismatch repair system specifically by
graded deficiency of LPMR (long-patch mismatch repair) which allows
interspecies recombinations and by genomic associations (hitchhiking) with
favorable mutations generated by mutator activity. SOS regulon agents are “turn
on” and LPMR is “turn off” via multi-step procedure. Processes of these agents
lead to instant evolution and
completely new genes and sequences that have not been in preexisting library
(or database). Agents becomes specialists and through second-order selection
rapidly converge to the solution. Adaptation is reachable by specifically
nested favorable mutations passing through about seven iterations. Inducible
SOS agents are crucial for reducing cost of adaptive function as well as
targeted hypermutable sequences.
Implications and applications:a)Computing-Conventional
models of recursive and subrecursive algorithms include an extra condition
where the algorithm has to stop to give a result. But it is not necessery any
more. People are working with displays already, and they can be satisfied when
the (printed) results are good enough, even if another, posibly better, result
may come in the future. Furthermore, usual notion about solving complex
problem, are in the course of higher processing power and capacity. But even
when we reach the limit of silicon based techology (some projection said 2012),
recursive algorithms will be still limited requesting infinite time for solving
complex problem. Instead of “brute force” and exhaustive search through the
universum space of all the alternatives, superrecursive algorithms supported by
EDC model focus on improving program procedure.
This form of computation could
be avaliable before exotic technologies such as molecular DNA or quantum
computing. Moreover, human creativity multiplied by this computation will allow
human-computer cooperation to an unimaginable degree. This approach opens new
perspectives for artificial intelligence methods and, for numerous disciplines
and human activities, potential applications appear almost limtless.
b)Biotechnology-After we have taken concepts from several
remarkable lessons of evolution, now we can go back to biotechnology and
experimental evolution with a new tool. By introducing EDC model we could
simulate bacterial mission surveyeing through several layers: generate
diversity and extract the desired gene from the library of genes and possibly
new genes that code for improved proteins. EDC model can be developed very
specifically according to some specific laboratory research and could be used
for probabilistic models of phylogenetic trees; for finding interactive
proteins; or for searching tiny genetic differences among individuals called
single-nucleotide polymophism (SNP’s). It could be expanded to include
experimental design. What we are going to get is hypotheses that needs to be
tested. EDC assigment is for wide range data/solutions areas where clasical
recursive models need infinite time.
Keywords: evolutionary directed computation (EDC); agents
of evolvability; SOS-regulon agents(SOS); hypermutable agents (HMS, HRS);
hitch-hiking(hh); mutator agents; mismatch repair agents (long-patch,LPMR &
short-patch,SPMR); second-order selection.