PubMed Health⌕ Search

PubMed · 11742671

Suspension array technology: evolution of the flat-array paradigm.

Abstract

Suspension arrays of microspheres analyzed using flow cytometry offer a new approach to multiplexed assays for large-scale screening applications. By optically encoding micron-sized polymer particles, suspension microarrays can be created to enable highly multiplexed analysis of complex samples. Each element in the array is comprised of a subpopulation of particles with distinct optical properties and each array element bears a different surface receptor. Nucleic acids, proteins, lipids or carbohydrates can serve as receptors to support the analysis of a wide range of biomolecular assemblies, and applications in genomic and proteomic research are being developed. Coupled with recent innovations for rapid serial analysis of samples, molecular analysis with microsphere arrays holds significant potential as a general analysis platform for both research and clinical applications.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

John P Nolan, Larry A Sklar. 2002. Suspension array technology: evolution of the flat-array paradigm.. https://doi.org/10.1016/s0167-7799(01)01844-3

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Surveying a local fitness landscape of a protein with epistatic sites for the study of directed evolution.

We present a method for analysis of a fitness landscape of a biopolymer with significantly epistatic sites. The analysis is based on a quasi-additive fitness model. The fitness model is constructed with additive terms conducted by "site-fitness" and epistatic terms conducted by "pair-fitness," where the site-fitness is a fitness contribution from an independent residue and the pair-fitness is a fitness contribution from a pair of epistatic residues. As a case study, we analyzed the sequence-fitness data for 45 clones of thermostable prolyl endopeptidase mutants. They were generated by a mutation scrambling method, which can accumulate advantageous mutations. The fitness contributions from 14 single-point mutations including E67Q and Q656R were identified by the analysis. As a result, we found that the fitness model with a significant epistatic term by a pair of the 67th site and 656th site was in good agreement with the experimental data and that the explored landscape in the binary 14-dimensional sequence space is still a mountainous landscape with twin peaks. The validity was supported by the analysis of mutant fitness distributions derived from another mutation scrambling experiment and by (3D) structural data.

Directed Molecular Evolution↗

Genome shuffling leads to rapid phenotypic improvement in bacteria.

For millennia, selective breeding, on the basis of biparental mating, has led to the successful improvement of plants and animals to meet societal needs. At a molecular level, DNA shuffling mimics, yet accelerates, evolutionary processes, and allows the breeding and improvement of individual genes and subgenomic DNA fragments. We describe here whole-genome shuffling; a process that combines the advantage of multi-parental crossing allowed by DNA shuffling with the recombination of entire genomes normally associated with conventional breeding. We show that recursive genomic recombination within a population of bacteria can efficiently generate combinatorial libraries of new strains. When applied to a population of phenotypically selected bacteria, many of these new strains show marked improvements in the selected phenotype. We demonstrate the use of this approach through the rapid improvement of tylosin production from Streptomyces fradiae. This approach has the potential to facilitate cell and metabolic engineering and provide a non-recombinant alternative to the rapid production of improved organisms.

Directed Molecular Evolution↗

Increasing the thermal stability of an oligomeric protein, beta-glucuronidase.

The reporter enzyme beta-glucuronidase was mutagenized and evolved for thermostability. After four cycles of screening the best variant was more active than the wild-type enzyme, and retained function at 70 degrees C, whereas the wild-type enzyme lost function at 65 degrees C. Variants derived from sequential mutagenesis were shuffled together, and re-screened for thermostability. The best variants retained activities at even higher temperatures (80 degrees C), but had specific activities that were now less than that of the wild-type enzyme. The mutations clustered near the tetramer interface of the enzyme, and many of the evolved variants showed much greater resistance to quaternary structure disruption at high temperatures, which is also a characteristic of naturally thermostable enzymes. Together, these results suggest a pathway for the evolution of thermostability in which enzymes initially become stable at high temperatures without loss of activity at low temperatures, while further evolution leads to enzymes that have kinetic parameters that are optimized for high temperatures.

Directed Molecular Evolution↗