Chapter 20, Problem 7RQ

Summary Introduction

Higher concentration of Mercury ion (Hg²⁺) and Methylmercury (CH₃Hg⁺) are very toxic to both macroorganisms and microorganisms. Many gram-positive and gram-negative bacteria can convert these toxic forms to relatively less toxic or non-toxic forms. Mercury resistant bacteria use enzyme organomercury lyase to degrade toxic form such as CH₃Hg⁺ to Hg²⁺ and methane. These bacteria also employ the use of enzyme mercuric reductase to reduce Hg²⁺ to Hg⁰.