SUPPLEMENTARY DOCUMENTS Metaproteomics reveals functional differences in intestinal microbiota development of preterm infants Zwittink RD 1 , van Zoeren-Grobben D 2 , Martin R 3 , van Lingen RA 2 , Groot Jebbink LJ 2 , Boeren S 4 , Renes IB 3 , van Elburg RM 3,5 , Belzer C 1,* , Knol J 1,3,* 1. Laboratory of Microbiology, Wageningen University, Wageningen, the Netherlands 2. Princess Amalia Dpt of Paediatrics, Dpt of Neonatology, Isala, Zwolle, The Netherlands 3. Nutricia Research, Utrecht, The Netherlands 4. Laboratory of Biochemistry, Wageningen University, Wageningen, The Netherlands 5. Emma Children’s Hospital, AMC, Amsterdam, The Netherlands * These authors contributed equally Running title: Microbiota development in preterm infants Corresponding Author: Clara Belzer Laboratory of Microbiology, Wageningen University; Stippeneng 4, 6708WE, Wageningen, The Netherlands T: +31 483751 E-mail: clara.belzer@wur.nl SUPPLEMENTARY DOCUMENTS