Shiga toxin 1 gene (stx1)

The stx1 virulence gene DNA encodes Shiga toxin 1, a potent AB5-type exotoxin primarily produced by Shiga toxin-producing Escherichia coli (STEC) and Shigella dysenteriae (StatPearls, 2023). This gene is typically carried on lambdoid prophages integrated into the bacterial chromosome, and its expression is often regulated by the bacterial SOS response system (NCBI, 2023). While the DNA sequence itself is a critical diagnostic biomarker used in clinical and food microbiology to identify pathogenic strains via PCR, it is not a direct therapeutic target for conventional drugs (CDC, 2023). The protein product of this gene consists of an enzymatic A subunit and five B subunits that facilitate entry into host cells by binding to globotriaosylceramide (Gb3) receptors (UniProt, 2024). Once inside the cytoplasm, the A subunit inactivates the 60S ribosomal subunit, halting protein synthesis and leading to cell death, which can manifest clinically as hemorrhagic colitis or life-threatening hemolytic uremic syndrome (PubMed, 1988). Therapeutic challenges include the fact that certain antibiotics can trigger the SOS response, paradoxically increasing stx1 gene expression and toxin release (Mayo Clinic, 2023).

Other names

stx1 geneShiga-like toxin 1 geneslt1verotoxin 1 genestxA1stxB1

The stx1 gene encodes the Shiga toxin 1 protein, which functions as an N-glycosidase that removes a specific adenine residue from the 28S ribosomal RNA of the 60S subunit, thereby inhibiting host cell protein synthesis (Endo et al., 1988; StatPearls, 2023).