Accepted Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/1873- 3468.12630 This article is protected by copyright. All rights reserved. Received Date : 12-Jan-2017 Revised Date : 20-Feb-2017 Accepted Date : 16-Mar-2017 Article type : Research Letter Modulation of E. coli serine acetyltransferase catalytic activity in the cysteine synthase complex Roberto Benoni 1#° , Omar De Bei 2° , Gianluca Paredi 3 , Christopher S. Hayes 4,5 , Nina Franko 2 , Andrea Mozzarelli 2,6,7 , Stefano Bettati 1,6 , Barbara Campanini 2* 1- Dipartimento di Neuroscienze, 2- Dipartimento di Farmacia and 3- Centro Interdipartimentale SITEIA.PARMA, Università di Parma, Parma, Italy. 4- Department of Molecular, Cellular and Developmental Biology and 5- Biomolecular Science and Engineering Program, University of California, Santa Barbara, Santa Barbara, CA USA. 6- National Institute for Biostructures and Biosystems, Rome, Italy. 7- Istituto di Biofisica, CNR, Pisa, Italy. # Present address: Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Praha, Czech Republic °The authors contributed equally to the work