tORF_103888 microprotein

Same-strand overlap (alternative frame) existence proven (MS) function unknown 91 aa

A non-canonical small protein (smORF) excluded from the H37Rv annotation, detected by proteogenomics with a high-confidence peptide-spectrum match. It is served here as part of a separate microproteome track: it is not one of the 3906 canonical genes and does not count in the dark stock. Its existence is proven; its molecular function is unknown. It lies on the same strand within espI, i.e. an alternative reading frame of a known gene (dual coding) rather than a new locus.

Evidence & coordinates

Detection method	MS peptide-spectrum (compendium)
Existence evidence	high-confidence peptide-spectrum match (Spectrum Forest hc) (tier T1)
Cross-validation	no Ribo-RET footprint at this start (Smith et al. 2022). Not informative on its own: measured genome-wide, this Ribo-RET dataset recovers only 29.1 % of annotated H37Rv starts (1136/3906), so its absence here does not argue against this microprotein — existence is already established by the MS evidence above. (P20.5)
H37Rv coordinates	4354158–4354430 (+ strand)
Length	91 amino acids
Start codon	TTG
Shine-Dalgarno	SD absent
Folding free energy	0.0
Predicted localisation	Cytoplasmic (1.93)
Conservation	homologues detected in Actinobacteria, Mycobacteria
Overlaps locus	espI (Rv3876) — by genomic geometry

Sequence

MGACVDANQPGPVTRREVRAGPARSSPPQSPRVVSDRRRRSQRWGWQNHADSSVGVDVGSGAGRPDPGSRRGSRRRKPRRSGRATIGRDHR

Source: de Souza EV et al., Sci Rep 2024;14:31186 (doi:10.1038/s41598-024-82465-w); proteogenomics microprotein compendium. Overlap class is assigned by geometry against the H37Rv CDS set, not by the source's own label. ← all microproteins