Question

A peroxo- ligand in this coordination complex is degraded to a single redox-active oxygen atom in “compound I” (“compound one”), which goes on to hydroxylate C-H bonds. Unlike typical square planar complexes, this complex’s d-z-squared orbital lies above the d-sub-xy orbital in energy due to repulsion from a proximal histidine. This complex’s transition from a high-spin domed configuration to a low-spin planar configuration corresponds to a larger system’s T state and (*) R state. This cofactor for cytochrome P450s is metabolized to a “verdo-“ form before being cleaved to form biliverdin and then excreted as bilirubin. Due to pi backbonding, this complex undesirably binds very strongly to CO. For 10 (-5[1])points, name this iron-porphyrin complex, (-5[1])four of which appear in a namesake protein (-5[1])that binds molecular oxygen in red blood cells. ■END■ (10[1]0[4])

ANSWER: heme [or haem; accept oxo-heme; accept heme B; prompt on hemoglobin or oxohemoglobin or carboxyhemoglobin by asking “what coordination complex is a part of hemoglobin?”]
<JZ, Chemistry>
= Average correct buzz position

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Buzzes

PlayerTeamOpponentBuzz PositionValue
Joanna XiaoGeorgia Tech DMilton106-5
Matthew SumanenGeorgia Tech BGeorgia Tech C111-5
Adhrit YadavLambertInnovation Academy B119-5
Alex ThomasGeorgia Tech CGeorgia Tech B12810
Towery McNeilMississippi StateInnovation Academy C1280
Arjun NairInnovation Academy CMississippi State1280
Ian Droessler WilsonInnovation Academy BLambert1280
Darren KellisMiltonGeorgia Tech D1280

Summary

2024 ARCADIA at UC Berkeley2024-12-06Y2100%0%50%99.00
2024 ARCADIA at GT2024-12-06Y425%0%75%128.00
2024 ARCADIA at Warwick2024-12-06Y5100%0%20%107.60