Chromosomes with multiple DNA replication origins are a hallmark of Eukaryotes and some Archaea. All eukaryal nuclear replication origins are defined by the origin recognition complex (ORC) that recruits the replicative helicase MCM(2-7) via Cdc6 and Cdt1. We find that the three origins in the single chromosome of the archaeon Sulfolobus islandicus are specified by distinct initiation factors. While two origins are dependent on archaeal homologs of eukaryal Orc1 and Cdc6, the third origin is instead reliant on an archaeal Cdt1 homolog. We exploit the nonessential nature of the orc1-1 gene to investigate the role of ATP binding and hydrolysis in initiator function in vivo and in vitro. We find that the ATP-bound form of Orc1-1 is proficient for replication and implicates hydrolysis of ATP in downregulation of origin activity. Finally, we reveal that ATP and DNA binding by Orc1-1 remodels the protein's structure rather than that of the DNA template.

Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the intestine of warm-blooded organisms. Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans. Here, we present the complete genome sequence of Escherichia coli LCT-EC106, which was isolated from CGMCC 1.2385.

Here we report the draft genome sequence of one Acinetobacter genomic species 3 strain, D499, which harbors the bla(NDM-1) gene. The total length of the assembled genome is 4,103,824 bp, and 3,896 coding sequences (CDSs) were predicted within the genome. A previously unreported bla(NDM-1)-bearing plasmid was identified in this strain.

An outbreak caused by Shiga-toxin–producing Escherichia coli O104:H4 occurred in Germany in May and June of 2011, with more than 3000 persons infected. Here, we report a cluster of cases associated with a single family and describe an open-source genomic analysis of an isolate from one member of the family. This analysis involved the use of rapid, bench-top DNA sequencing technology, open-source data release, and prompt crowd-sourced analyses. In less than a week, these studies revealed that the outbreak strain belonged to an enteroaggregative E. coli lineage that had acquired genes for Shiga toxin 2 and for antibiotic resistance.