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J Khodor

Publications and source records attributed to J Khodor.

2 recordsLinked to original sources

Design and implementation of computational systems based on programmed mutagenesis.

In a new system for DNA computation called programmed mutagenesis, DNA strands are rewritten according to 'rules' that are sequence specific. In a programmed mutagenesis reaction DNA sequences undergo programmed changes, and these changes are implemented by an in-vitro mutagenesis system that is based on thermal cycling the rewriting reaction. We describe experimental results that demonstrate the key aspects of programmed mutagenesis. These results include the creation of full-length product DNA molecules that have embedded rewriting, the ability for later sequence changes to depend on earlier sequence changes, and the ability for multiple oligonucleotides to be active in close proximity on a template sequence. We also discuss the application of programmed mutagenesis to computational problems.

Animals↗

Automated constraint-based nucleotide sequence selection for DNA computation.

We present techniques for automating the design of computational systems built using DNA, given a set of high-level constraints on the desired behavior and performance of the system. We have developed a program called SCAN that exploits a previously implemented computational melting temperature primitive to search a 'nucleotide space' for sequences satisfying a pre-specified set of constraints, including hybridization discrimination, primer 5' end and 3' end stability, secondary structure reduction, and prevention of oligonucleotide dimer formation. The first version of SCAN utilized 24 h of computer time to search a space of over 7.5 billion unary counter designs and found only nine designs satisfying all of the pre-specified constraints. One of SCAN's designs has been implemented in the laboratory and has shown a marked improvement in performance over the products of previous attempts at manual design. We conclude with some novel ideas for improving the overall speed of the program that offer the promise of an efficient method for selecting optimal nucleotide sequences in an automated fashion.

Animals↗