%0 Journal article
%A Lumpe, Henning
%A Mayer, Peter
%A Daumann, Lena J.
%T Crystal structure of a calcium(II)–pyrroloquinoline quinone (PQQ) complex outside a protein environment
%R 10.23689/fidgeo-4206
%J Acta Crystallographica Section C
%V 76
%N 12

%I 5 Abbey Square%C Chester, Cheshire CH1 2HU, England
%X Pyrroloquinoline quinone (PQQ) is an important cofactor of calcium‐ and lanthanide‐dependent alcohol dehydrogenases, and has been known for over 30 years. Crystal structures of Ca–MDH enzymes (MDH is methanol dehydrogenase) have been known for some time; however, crystal structures of PQQ with biorelevant metal ions have been lacking in the literature for decades. We report here the first crystal structure analysis of a Ca–PQQ complex outside the protein environment, namely, poly[[undecaaquabis(μ‐4,5‐dioxo‐4,5‐dihydro‐1H‐pyrrolo[2,3‐f]quinoline‐2,7,9‐tricarboxylato)tricalcium(II)] dihydrate], {[Ca3(C14H3N2O8)2(H2O)11]·2H2O}n. The complex crystallized as Ca3PQQ2·13H2O with Ca2+ in three different positions and PQQ3−, including an extensive hydrogen‐bond network. Similarities and differences to the recently reported structure with biorelevant europium (Eu2PQQ2) are discussed.
%U http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/8546
%~  FID GEO-LEO e-docs