Complete Genome Sequence of Streptococcus anginosus J4211, a Clinical Isolate.

Streptococcus anginosus is an opportunistic human pathogen that causes abscesses of the brain, liver, and other organs. Here, we announce the complete genome sequence of a clinically isolated strain of S. anginosus J4211. The genome sequence contains two prophages and multiple mobile genetic elements.

GENOME ANNOUNCEMENT

Streptococcus anginosus belongs to the S. anginosus group (SAG), a subgroup of viridans streptococci. This group includes two other species, Streptococcus intermedius and Streptococcus constellatus (1, 2). These streptococci are typically commensal human flora of the oral cavity and gastrointestinal and genital tracts (3). However, they can occasionally cause opportunistic infections, particularly brain and liver abscesses, and are emerging pathogens in cystic fibrosis patients (4, 5). S. anginosus strain J4211 was originally a clinical isolate from the University of Texas Health Sciences Center at San Antonio, San Antonio, TX.

The strain was grown in Todd-Hewitt broth with 2% yeast extract (THY) broth supplemented with 5% heat-inactivated horse serum (THY-HS) overnight at 37°C. Chromosomal DNA was isolated as previously described (6, 7). The DNA library was prepared using the Nextera DNA library preparation kit (Illumina, Inc., San Diego, CA), and library quality was checked with an Agilent high-sensitivity DNA chip. Genome sequencing was performed by the Illumina MiSeq using paired-end 250-bp sequencing with high coverage (600-fold) at the University of Oklahoma Health Sciences Center, Laboratory for Genomics and Bioinformatics, Oklahoma City, OK. DNA assembly was done using the software package Geneious. Sequence gaps were closed by PCR amplification. Gene annotation was performed by the Rapid Annotations using Subsystems Technology (RAST) pipeline (8, 9). Genome annotation was completed using Artemis software (10) and a BLAST search.

The complete genome sequence of S. anginosus J4211 contains 1,924,513 bp, with a G+C content of 38.99%. The number of predicted coding regions is 1,926, with 13 rRNA genes and 60 tRNA genes. Analysis using the Web-based tool IslandViewer (11) revealed seven genomic islands, including mobile genetic elements and incomplete prophages. The PHAge Search Tool (PHAST), another Web-based program, confirmed the presence of two incomplete prophages (positions 120772 to 153677 and 1362153 to 1402752) (12). There are three clustered regularly interspaced short palindromic repeat (CRISPR) regions (positions 384703 to 385609, 910080 to 911303, and 1299282 to 1299517) in the genome identified by CRISPRFinder (13). The complete capsular polysaccharide (CPS) locus, as mentioned by Tsunashima et al. (14), is present in the genome sequence (positions 1789505 to 1820948). The genome sequence of this S. anginosus strain will help us in the future to understand the pathogenic mechanisms of this organism.

Nucleotide sequence accession number.

The complete genome sequence of S. anginosus J4211 has been deposited at GenBank under the accession number no. CP012805. This paper describes the first version of the genome.