Complete Genome Sequence of Chesapeake Bay Winter <italic toggle='yes'>Synechococcus</italic> sp. Strain CBW1107, a Member of Subalpine Cluster II

Here, we report the complete genome sequence of psychrotolerant Synechococcus sp. strain CBW1107, which was isolated from the Chesapeake Bay in winter. CBW1107 is a member of picocyanobacterial subalpine cluster II and exhibits greater cold tolerance than do most coastal and marine Synechococcus strains. The Chesapeake Bay (CB) is a large temperate estuary with strong seasonal variation of water temperature (0 to 28°C). The picocyanobacterial abundance in the CB varies from a few hundred cells per ml in winter to over 1 million cells per ml in summer (1). Distinct picocyanobacterial populations in winter and summer were found in the CB (2). Seventeen strains of Synechococcus were isolated from the Baltimore Inner Harbor in winter (3). These winter isolates are able to grow at low temperatures (4°C and 10°C) at which many coastal and open-ocean Synechococcus strains cannot survive. Synechococcus sp. strain CBW1107 is one of five CB winter isolates clustered in subalpine cluster II, which contains picocyanobacteria isolated from subalpine lakes, the Arctic Ocean, the Baltic Sea, and Long Island Sound (3). CBW1107 was grown in SN15 medium (3). For DNA extraction, 20ml of an exponential-phase culture (optical density at 750 nm [OD750], 0.8) was centrifuged at 10,000 g for 10min. Cell pellets were ground with liquid nitrogen, transferred into 2-ml tubes with cetyltrimethylammonium bromide (CTAB) lysis buffer (4), and then incubated for 60min at 65°C in a water bath. Genomic DNA was then extracted by using the phenol-chloroform method described by Kan et al. (5). The complete genome sequence of CBW1107 was obtained using a combination of Illumina HiSeq and PacBio Sequel platforms at the Beijing Genomics Institute (BGI) (Shenzhen, China). The details of the sequencing reads can be found in Table 1. Default parameters were used for all software unless otherwise noted for the sequence processing and genome analyses. Four single-molecule real-time (SMRT) cell zero-mode waveguide arrays for sequencing were used with the PacBio platform to generate the subread set. The raw reads from the Illumina sequencing with an average 2 150-bp paired-end sequencing kit with low quality (score of #20) or high N nucleotide percentage (.10%), adapter reads, and duplicate reads were removed to obtain clean reads by using SOAPnuke version 1.5. 6. For PacBio raw sequences, adapters and poor-quality reads were cut from polymerase reads to generate multiple subreads. Citation Fucich D, Xu Y, Sosa A, Zhang R, Jiao N, Chen F. 2021. Complete genome sequence of Chesapeake Bay winter Synechococcus sp. strain CBW1107, a member of subalpine cluster II. Microbiol Resour Announc 10:e01399-20. https://doi.org/10.1128/MRA.01399-20. Editor Frank J. Stewart, Georgia Institute of Technology Copyright © 2021 Fucich et al. This is an openaccess article distributed under the terms of the Creative Commons Attribution 4.0 International license. Address correspondence to Feng Chen, chenf@umces.edu. Received 8 December 2020 Accepted 26 January 2021 Published 18 February 2021 Volume 10 Issue 7 e01399-20 mra.asm. org 1 GENOME SEQUENCES