Abstract Background N-hydroxylated base analogs. such as 6-hydroxylaminopurine (HAP) and 2-amino-6-hydroxylaminopurine (AHA). are strong mutagens in various organisms due to their ambiguous base-pairing properties. The systems protecting cells from HAP and related noncanonical purines in Escherichia coli include specialized deoxyribonucleoside triphosphatase RdgB. https://tonerparts.shop/product-category/shipping-cost/