Phycocordibacterales ord. nov.

Submitted by Jonas, Lauren

Order Phycocordibacterales

Etymology: [Phy.co.cor.di.bac.ter.ales] L. masc. n. Phycocordibacter, referring to the type genus Phycocordibacter; -ales, ending to denote an order; N.L. fem. pl. n. Phycocordibacterales, the Phycocordibacter order
Nomenclatural type: Genus Phycocordibacter
Description: This is an order within the Patescibacteria phylum, some of whose members are symbionts of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 for carbon mitigation research.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49171

Family Phycocordibacteraceae

Etymology: [Phy.co.cor.di.bac.ter.a'ce.ae] L. masc. n. Phycocordibacter, referring to the type genus Phycocordibacter; -aceae, ending to denote a family; N.L. fem. pl. n. Phycocordibacteraceae, the Phycocordibacter family
Nomenclatural type: Genus Phycocordibacter
Description: This is a family within the Patescibacteria phylum, some of whose members are symbionts of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 for carbon mitigation research.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales » Phycocordibacteraceae
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49183

Genus Minusculum

Etymology: [Mi.nu.scu.lum] L. neut. n. Minusculum, rather small, referring to the genome size
Nomenclatural type: Species Minusculum obligatum^Ts
Description: This is a genus within the Patescibacteria phylum, one of whose members is a symbiont of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 for carbon mitigation research.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales » Phycocordibacteraceae » Minusculum
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49177

Genus Phycocordibacter

Etymology: [Phy.co.cor.di.bacter] Gr. neut. n. phykos, seaweed or algae; L. neut. n. cordis, the most central part or the heart; N.L. masc. n. bacter, a rod; N.L. masc. n. Phycocordibacter, A core bacteria of a microalgal culture
Nomenclatural type: Species Phycocordibacter aenigmaticus^Ts
Description: This is a genus within the Patescibacteria phylum, one of whose members is symbionts of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 for carbon mitigation research.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales » Phycocordibacteraceae » Phycocordibacter
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49176

Species Minusculum obligatum^Ts

Etymology: [o.bli.ga'tum] L. neut. adj. obligatum, to bind, oblige, or require
Nomenclatural type: NCBI Assembly: GCA_045401155.1 ^Ts
Description: This is a Patescibacteria group bacterium that is a symbiont of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 in our laboratory for carbon mitigation research. This bacterium was found at the 1 L and 500 L scale and has a genome size of 578,798 bp. It is a dominant bacterium based on relative abundance of the 16S rRNA gene at both scales regardless of whether the algae are bubbled with 10% CO2 or ambient air. Its hyper reduced genome suggests its symbiosis may be obligatory.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales » Phycocordibacteraceae » Minusculum » Minusculum obligatum^Ts
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49173

Species Phycocordibacter aenigmaticus^Ts

Etymology: [ae.nig.ma'ti.cus] L. masc. adj. aenigmaticus, enigmatic or obscure
Nomenclatural type: NCBI Assembly: GCA_045401115.1 ^Ts
Description: This is a Patescibacteria group bacterium that is a symbiont of the microalgae Nannochloropsis oceanica strain IMET1 and Tetradesmus obliquus strain HTB1. Both microalgae are grown with 10% CO2 in our laboratory for carbon mitigation research. This bacterium was found at the 1 L and 500 L scale and has a genome size of 721,362 bp.
Classification: Bacteria » Patescibacteriota » “Paceibacteria” » Phycocordibacterales » Phycocordibacteraceae » Phycocordibacter » Phycocordibacter aenigmaticus^Ts
References: Effective publication: Jonas et al., 2025 [1]
Registry URL: https://seqco.de/i:49172

References

Jonas et al. (2025). Two novel Patescibacteria: Phycocordibacter aenigmaticus gen. nov. sp. nov. and Minusculum obligatum gen. nov. sp. nov., both associated with microalgae optimized for carbon dioxide sequestration from flue gas. mBio. DOI:10.1128/mbio.01231-25

Register List Certificate of Validation

On behalf of the Committee on the Systematics of Prokaryotes Described from Sequence Data (SeqCode Committee), we hereby certify that the Register List seqco.de/r:ywe1blo2 submitted by Jonas, Lauren and including 6 new names has been successfully validated.

Date of Priority: 2025-06-17 05:37 UTC

DOI: 10.57973/seqcode.r:ywe1blo2