Quinone Sites (image) Arizona State University Share Print E-Mail Caption Arrangement of the cofactors in the HbRC, along with a possible position of the quinone cofactor, shown fit in the electron density of an unknown molecule (Gisriel et al., 2017). School of Molecular Sciences @ Arizona State University. Credit Greg Orf Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.