Ammonia monooxygenase (AMO) (AMO)

Ammonia monooxygenase (AMO) is a multi-subunit, membrane-bound enzyme found in ammonia-oxidizing bacteria (AOB), such as Nitrosomonas eutropha D23 [UniProt P13912]. It catalyzes the rate-limiting step of nitrification, the oxidation of ammonia (NH3) to hydroxylamine (NH2OH), using sweat-derived ammonia as a metabolic substrate [AOBiome, 2023]. This enzymatic activity is central to the therapeutic mechanism of live biotherapeutic products like B244, which are designed to restore the skin's natural microbiome and chemical balance. The subsequent conversion of hydroxylamine to nitrite and nitric oxide (NO) provides anti-inflammatory, antimicrobial, and vasodilatory benefits to the host [PubMed: 29164631]. By reducing skin pH and producing NO, AMO helps alleviate symptoms of inflammatory dermatological conditions such as acne vulgaris, rosacea, and atopic dermatitis [ClinicalTrials.gov: NCT04490109]. Additionally, the production of nitric oxide by this enzyme may have systemic effects, including the potential to lower blood pressure in hypertensive individuals [AOBiome, 2023].

Other names

Ammonia oxygenaseAmoA/AmoB/AmoC complexMethane monooxygenase-like enzyme

Ammonia monooxygenase catalyzes the oxidation of ammonia to hydroxylamine, which is subsequently converted to nitrite and nitric oxide; these products modulate the skin microenvironment by reducing inflammation, inhibiting pathogenic bacterial growth, and promoting vasodilation [AOBiome, 2023; PubMed: 29164631].