Table 1. Definitions of terms and counts for locus and genome categories analyzed using LoClass.
| Term | Definition | Count |
| Locus Super-type | The largest cluster of loci where all contained loci encode the same signature enzyme or are syntenic to these loci while encoding no alternative signature enzyme. | 15 |
| Locus Type | A more stringent cluster of loci; in addition to conserved signature enzymes, these loci typically are syntenic to one another, indicating common origin. | 23 |
| Locus (Sub)type | The most stringent clustering of loci, where many syntenic loci of the same type are separated into smaller groups; these typically vary by genes encoding ancillary functions. | 30 |
| Prospective BMC Locus | Region of a genome including BMC shell protein genes within 20 kb of each other and all other genes within 10 kb upstream and downstream. | 580 |
| Envelope | Region of a Prospective BMC Locus that includes only the BMC shell protein genes and genes encoded between them. | - |
| Satellite loci | Prospective BMC Loci that are predicted to encode a subset of shell components for a BMC and no other BMC-related genes (Materials and Methods). | 149 |
| Satellite-like loci | Prospective BMC Loci that meet most but not all of the criteria established for satellite loci or encode other BMC-related genes. | 21 |
| Confirmed BMC Loci | All Prospective BMC Loci which are of the same Locus Type as a locus whose function has been experimentally elucidated. | 335 |
| Candidate BMC Loci | All Prospective BMC Loci that are not putative satellite, satellite-like, or Confirmed BMC Loci. | 75 |
| Carboxysome loci | Confirmed Loci encoding the carboxysome. | 87 |
| Metabolosome loci | Candidate/Confirmed Loci that, of the core metabolosome enzymes, encode at least a core AldDH or are members of a Locus Type where the majority of loci do. These loci presumably encapsulate catabolic reactions (Fig. 1B). | 312 |
| Metabolosome loci with an incomplete core | Metabolosome loci that are of a Locus Type where the majority of loci do not encode a core AlcDH and/or PTAC. | 22 |
| BMC-containing genomes | Genomes that contain any Prospective BMC Loci. | 329 |
| Satellite-containing genomes | Genomes containing at least one putative satellite locus. | 77 |
Counts for Locus super-types, types, and sub-types include loci from IMG that were analyzed manually. Due to the fragmentation of most IMG loci, these were excluded from all other counts.