title: Efficient de novo assembly of single-cell bacterial genomes from short-read data sets.
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 uncultivated bacteria using only short reads, providing cell-specific genetic information absent from metagenomic studies.
authors.affiliation: Department of Computer Science, University of California, La Jolla, CA, USA.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Chitsaz
authors.forename: Joyclyn L
authors.initials: JL
authors.lastname: Yee-Greenbaum
authors.forename: Glenn
authors.initials: G
authors.lastname: Tesler
authors.forename: Mary-Jane
authors.initials: MJ
authors.lastname: Lombardo
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Dupont
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Badger
authors.forename: Mark
authors.initials: M
authors.lastname: Novotny
authors.forename: Douglas B
authors.initials: DB
authors.lastname: Rusch
authors.forename: Louise J
authors.initials: LJ
authors.lastname: Fraser
authors.forename: Niall A
authors.initials: NA
authors.lastname: Gormley
authors.forename: Ole
authors.initials: O
authors.lastname: Schulz-Trieglaff
authors.forename: Geoffrey P
authors.initials: GP
authors.lastname: Smith
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Evers
authors.forename: Pavel A
authors.initials: PA
authors.lastname: Pevzner
authors.forename: Roger S
authors.initials: RS
authors.lastname: Lasken
mesh_terms: D000465:Algorithms; D001419:Bacteria / Q000166:cytology* / Q000235:genetics*; D001483:Base Sequence; D020451:Contig Mapping; D030561:Databases, Nucleic Acid; D020564:Deltaproteobacteria / Q000166:cytology / Q000235:genetics; D004926:Escherichia coli / Q000166:cytology / Q000235:genetics; D016680:Genome, Bacterial / Q000235:genetics*; D016013:Likelihood Functions; D017422:Sequence Analysis, DNA / Q000379:methods*; D059010:Single-Cell Analysis / Q000379:methods*; D013211:Staphylococcus aureus / Q000166:cytology / Q000235:genetics