Special proteins – known as membrane transporters – are of key importance for the mobility of sperm cells. A research team from the Heidelberg University Biochemistry Center (BZH) headed by Prof. Dr Cristina Paulino has, with the aid of cryo-electron microscopy, for the first time succeeded in decoding the structure of such a transporter and its mechanism. According to the researchers, these findings will enable a better understanding of the molecular foundations of reproductive capacity and could, in the long term, contribute to developing new approaches to treating fertility disorders and new methods of specific contraception.