{"rfam": {"acc": "RF00521", "id": "SAM_alpha", "description": "Alpha-proteobacteria SAM riboswitch aptamer", "comment": "This family is a riboswitch found predominantly in alpha-proteobacteria that binds S-adenosyl methionine (SAM). Its structure and sequence appear to be unrelated to the SAM riboswitch Rfam:RF00162 found in Gram-positive bacteria. This SAM riboswitch is located upstream of the metA and metC genes in Agrobacterium tumefaciens, and other methionine and SAM biosynthesis genes in other alpha-proteobacteria. Like the other SAM riboswitch, it probably functions to turn off expression of these genes in response to elevated SAM levels.", "curation": {"author": "Barrick JE, Corbino KA, Breaker RR", "seed_source": "Barrick JE", "num_seed": 40, "num_full": 1184, "num_species": 1006, "type": "Cis-reg; riboswitch;", "structure_source": "Predicted; Barrick JE"}, "cm": {"build_command": "cmbuild -F CM SEED", "calibrate_command": "cmcalibrate --mpi CM", "search_command": "cmsearch --cpu 4 --verbose --nohmmonly -T 24.99 -Z 2958934 CM SEQDB", "cutoffs": {"gathering": 36.0, "trusted": 36.0, "noise": 35.9}}, "release": {"date": "2026-01-16", "number": "15.1"}, "clan": {"acc": null, "id": null}}}