Escherichia coli AY1

Escherichia coli is a highly diverse bacterial species found naturally in the human gut, where most strains are commensal — meaning they coexist with their host without causing harm.

Escherichia coli K12 is a non-pathogenic laboratory reference strain that has been central to molecular biology and genetics research since the mid-20th century.

Escherichia coli ATCC 8739 is a non-pathogenic, biosafety level 1 laboratory reference strain used extensively as a negative control or challenge organism in antimicrobial and microbiological assays.

Escherichia coli ATCC 35218 is a laboratory reference strain maintained by the American Type Culture Collection for standardized antimicrobial susceptibility testing; it carries a specific beta-lactamase gene making it u…

Escherichia coli BL21 is a laboratory expression host strain widely used in molecular biology for recombinant protein production; it is not a probiotic organism and is not used in human health supplementation.

Escherichia coli ATCC 25922 is a well-characterized reference strain used as a quality control organism in antimicrobial susceptibility testing and microbiological laboratory work — it is not a probiotic strain.