Bio Saga Blog - A Chronicle of Life Sciences & Informatics

Abstract 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 uncu...

While nonribosomal peptides (NRPs) are of tremendous pharmacological importance, there is currently no technology capable of high-throughput sequencing of NRPs. Difficulties in sequencing NRPs slow down the progress in elucidating the non-ribosomal genetic code and negatively affect various screening programs aimed at the discovery of natural compounds of medical importance. We propose to employ multi-stage mass-spectrometry (MS n ) for the data acquisition, followed by alignment-based heuristic algorithms for data analysis. Since mass spectrometry based analysis of NRPs is fast and inexpensive, this approach opens the possibility of high-throughput sequencing of many unknown NRPs accumulated in large screening programs. Do you want to know more?