Regnicoccus gen. nov. and Regnicoccus antarcticus comb. nov.

Ernster, Rodriguez-R, 2025: The genus Regnicoccus was proposed by Walter et al., 2017 on the basis of genomic analyses, and is part of “Cyanobiaceae” if considered a separate family (Panwar et al., 2022) or part of Synecococcaceae otherwise.

Ernster, Rodriguez-R, 2025: The genome assembly is established as type material, and the reference strain is WH 5701.

Coutinho et al., 2016: The phycobilisome pigmentation of this strain belongs to class 1. Bacteriocin gene clusters detected in this genome belong to class I. Type strain is WH5701(T), which has a genome of 3.28 Mbp with a GC content of 65.4% that encodes 3185 genes that include 593 diagnostic orthologous groups. Taxonomic affiliation to Parasynechococcus antarcticus WH5701 can be defined by the presence of Ammonium transporter, Ferric iron ABC transporter: ATP-binding protein, Ferric iron ABC transporter: iron-binding protein, Ferric iron ABC transporter: permease protein, Ferrous iron transport protein B, GlnN, NifS, NifU, Nitrate ABC transporter, PiuC, Protein PII, UreD, UreE, UreF, UreG, UrtA, UrtB, UrtC, UrtD, UrtE, phnE, phoB, phoH, phoR, pstA, pstB, pstC, pstS.

Walter et al., 2017: This species is characterized by α-carboxysome. Type strain is WH 5701, isolated from marine habitat in Long Island Sound, Connecticut, USA. The genome of this strain contains 3.28 Mbp (GC = 65.4%) harboring 2,917 coding DNA sequences.