miaB (P0AEI1) notes

Deep research was unavailable for this gene (falcon returned 403; asta returned nothing useful in
Phase 1 of the RADICAL_SAM project). The review was built from cached primary papers, the UniProt
record and QuickGO term lookups.

Function

• MiaB converts i6A37 to ms2i6A37 in tRNAs reading UNN codons. Genetic identification in
  S. typhimurium and E. coli: PMID:10572129
• The same paper argued MiaB did only thiolation: PMID:10572129. Overturned by in vitro reconstitution:
  PMID:15339930
• Two SAM per turnover: PMID:15339930
  Abstract does not name the organism; PubMed MeSH lists Escherichia coli Proteins (and
  Thermotoga maritima). Evidence code for the NEW SAM-binding row set to IDA on that basis.
• Fe-S: PMID:11882645; Cys157/161/164 required.
• Both clusters retained; exogenous sulfur: PMID:23542644 (T. maritima enzymes).
• Fe-S delivery: GrxD and NfuA bind MiaB; NfuA transfers its cluster PMID:23543739. The IPI protein binding row was removed as uninformative (MiaB is the cluster acceptor).
• Cytosol: PMID:18304323.

Term decisions

• Core MF GO:0035597; BP GO:0035600; CC GO:0005829; GO:0051539; NEW GO:1904047 (IDA PMID:15339930).
  Same terms as genes/human/CDK5RAP1 (MiaB-subfamily ortholog).
• GO:0030488 tRNA methylation (IMP) -> MODIFY GO:0035600 (lateral; GO:0035600 is not under GO:0030488
  in QuickGO). GO:0006400 -> GO:0035600. GO:0016740, GO:0035596, GO:0003824 -> GO:0035597.
  GO:0051536 -> GO:0051539. GO:0005737 -> GO:0005829.
• No translational-fidelity BP added: requirement, not participation; not in E. coli GOA.

Context

• Module modules/trna_ms2io6a37_hydroxylation (MiaE step, P. putida) treats MiaA/MiaB as upstream
  context; E. coli stops at ms2i6A (no MiaE).