Whole genome amplification by the multiple displacement amplification (MDA) method allows sequencing of DNA from single cells of bacteria that cannot be cultured. Assembling a genome is challenging, however, because MDA generates highly nonuniform coverage of the genome. Here we describe an algorithm tailored for short-read data from single cells that improves assembly through the use of a progressively increasing coverage cutoff. Assembly of reads from single Escherichia coli and Staphylococcus aureus cells captures >91% of genes within contigs, approaching the 95% captured from an assembly based on many E. coli cells. We apply this method to assemble a genome from a single cell of an uncultivated SAR324 clade of Deltaproteobacteria, a cosmopolitan bacterial lineage in the global ocean. Metabolic reconstruction suggests that SAR324 is aerobic, motile and chemotaxic. Our approach enables acquisition of genome assemblies for individual uncultivated bacteria using only short reads, providing cell-specific genetic information absent from metagenomic studies.
East meets West, yet another story of an successful Indian entrepreneur
HCL founder and chairman and chief strategy officer of HCL Technologies Shiv Nadar was named for the Padma Bhushan honour . Here is yet an interesting and inspiring story of another Shiva, to those aspiring a career in informatics as well as all aspiring entrepreneurs. In the 26 years since he first arrived at MIT as a freshman, V.A. Shiva Ayyadurai has earned four MIT degrees and started two multimillion dollar companies. This fall, he will use his most recent degree, a Ph.D. in computational systems biology, and a Fulbright Scholarship to explore one of his lifelong interests: the intersection of Eastern and Western medicine. Ayyadurai started dreaming as a child in India, where his grandfather was a farmer and his grandmother a shaman, or traditional healer. He became interested in medicine watching his grandmother diagnose and treat patients based on a system of "elements"--earth, water, fire, metal and wood. That approach may seem strange to Westerners, but "you...
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