10.1007\/s00775-022-01953-4<\/a><\/p>\nAuthors:<\/h4>\n
George E. Cutsail, R. Banerjee, Derek B. Rice, Olivia McCubbin Stepanic, John D. Lipscomb, Serena DeBeer<\/p>\n
Abstract:<\/h4>\n
Soluble methane monooxygenase (sMMO) facilitates the conversion of methane to methanol at a non-heme FeIV<\/sup>2<\/sub> intermediate MMOHQ<\/sub>, which is formed in the active site of the sMMO hydroxylase component (MMOH) during the catalytic cycle. Other biological systems also employ high-valent FeIV<\/sup> sites in catalysis; however, MMOHQ<\/sub> is unique as Nature’s only identified FeIV<\/sup>2<\/sub> intermediate. Previous 57<\/sup>Fe M\u00f6ssbauer spectroscopic studies have shown that MMOHQ<\/sub> employs antiferromagnetic coupling of the two FeIV<\/sup> sites to yield a diamagnetic cluster. Unfortunately, this lack of net spin prevents the determination of the local spin state (Sloc<\/sub>) of each of the irons by most spectroscopic techniques. Here, we use Fe K\u03b2 X-ray emission spectroscopy (XES) to characterize the local spin states of the key intermediates of the sMMO catalytic cycle, including MMOHQ<\/sub> trapped by rapid-freeze-quench techniques. A pure XES spectrum of MMOHQ<\/sub> is obtained by subtraction of the contributions from other reaction cycle intermediates with the aid of M\u00f6ssbauer quantification. Comparisons of the MMOHQ<\/sub> spectrum with those of known Sloc<\/sub> = 1 and Sloc<\/sub> = 2 FeIV<\/sup> sites in chemical and biological models reveal that MMOHQ<\/sub> possesses Sloc<\/sub> = 2 iron sites. This experimental determination of the local spin state will help guide future computational and mechanistic studies of sMMO catalysis.<\/p>\n","protected":false},"excerpt":{"rendered":"DOI: 10.1007\/s00775-022-01953-4 Authors: George E. Cutsail, R. Banerjee, Derek B. Rice, Olivia McCubbin Stepanic, John D. Lipscomb, Serena DeBeer Abstract: Soluble methane monooxygenase (sMMO) facilitates the conversion of methane to methanol at a non-heme FeIV2 intermediate MMOHQ, which is formed in the active site of the sMMO hydroxylase component (MMOH) during the catalytic cycle. Other […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-741","post","type-post","status-publish","format-standard","hentry","category-freeze-quench"],"_links":{"self":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts\/741","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=741"}],"version-history":[{"count":0,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts\/741\/revisions"}],"wp:attachment":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=741"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=741"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=741"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}