Work group Prof. Dr. Guntram Graßl

Medical Microbiome Research
Infections caused by enteropathogenic bacteria such as Salmonella are associated with high morbidity and mortality. Salmonella is taken up via contaminated food and water and invades the host’s gastrointestinal tract epithelium. Infections with enteropathogenic serovars lead to acute and chronic intestinal inflammation. The composition of the commensal intestinal microbiota plays an important role for the susceptibility to infection. Commensal microorganisms can either play a protective or harmful role. My laboratory’s research is aimed at elucidating the interactions of enteropathogenic bacteria (e.g. Salmonella, E. coli, C. difficile) with commensal microorganisms and the host. In close collaboration with the hospital clinics we are also looking for new therapeutic options to interfere with the disease process.

Our main research interests include how intestinal glycosyltransferases influence intestinal bacteria and the susceptibility to pathogens. Other projects investigate pathogenicity factors of the emerging Salmonella serovar S. Infantis and the host specificity of different narrow and broad host range serovars. In addition, we are studying the role of bacterial and host factors in acute and chronic bacteria-triggered inflammation and intestinal fibrosis.

 

These research projects are supported by grants of the DZIF, the German Research Foundation DFG (SFB 900), the Federal Ministry of Education and Research (Infect-ERA) and the Volkswagen Foundation.

Members of the Work Group Graßl

 

Most important publications:

  • Aviv G, Cornelius A, Davidovich M, Cohen H, Suwandi A, Galeev A, Steck N, Azriel S, Rokney A, Valinsky L, Rahav G, Grassl GA*, Gal-Mor O*.Differences in the expression of SPI-1 genes pathogenicity and epidemiology between the emerging Salmonella enterica serovar Infantis and the model Salmonella enterica serovar Typhimurium. J Infect Dis. 2019;220(6):1071-1081.

  • Suwandi A, Galeev A, Riedel R, Sharma S, Seeger K, Sterzenbach T, García Pastor L, Boyle EC, Gal-Mor O, Hensel M, Casadesús J, Baines JF, Grassl GA. Std fimbriae-fucose interaction increases Salmonella-induced intestinal inflammation and prolongs colonization. PLoS Pathog. 2019;15(7):e1007915.

  • Ehrhardt K, Steck N, Kappelhoff R, Stein S, Rieder F, Gordon IO, Boyle EC, Braubach P, Overall CM, Finlay BB, Grassl GA. Persistent Salmonella enterica Serovar Typhimurium Infection induces protease expression during intestinal fibrosis. Inflamm Bowel Dis. 2019. pii: izz070.                           

  • Schramm G, Suwandi A, Galeev A, Sharma S, Braun J, Claes AK, Braubach P, Grassl GA. Schistosome eggs impair protective Th1/Th17 immune responses against Salmonella infection. Front Immunol. 2018;9:2614.              

  • Schöttelndreier D, Seeger K, Grassl GA, Winny MR, Lindner R, Genth H. Expression and (lacking) internalization of the cell surface receptors of Clostridioides difficile Toxin B. Front Microbiol. 2018;9:1483.              

  • Aviv G, Elpers L, Mikhlin S, Cohen H, Zilber SV, Grassl GA, Rahav G, Hensel M, Gal-Mor O. The plasmid-encoded Ipf and Klf fimbriae display different expression and varying roles in the virulence of Salmonella enterica serovar Infantis in mouse vs. avian hosts. PLoS Pathogens, 2017; 13(8): e1006559.                  

  • Westphal A, Cheng W, Yu J, Grassl G, Krautkrämer M, Holst O, Föger N, Lee KH. Lysosomal trafficking regulator Lyst links membrane trafficking to toll-like receptor-mediated inflammatory responses. J Exp Med. 2017;214(1):227-244.       

  • Elhadad D, Desai P, Grassl GA, McClelland M, Rahav G, Gal-Mor O. Differences in host cell invasion and Salmonella Pathogenicity Island 1 Expression between Salmonella enterica Serovar Paratyphi A and Nontyphoidal S. Typhimurium. Infect Immun. 2016;84(4):1150-65.

  • Rausch P, Steck N, Suwandi A, Seidel JA, Künzel S, Bhullar K, Basic M, Bleich A, Johnsen JM, Vallance BA,  Baines JF, Grassl GA. 2015. Expression of the blood-group-related gene B4galnt2 alters susceptibility to Salmonella infection. PLoS Pathogens. 11 e1005008.

  • Grassl GA*, Valdez Y*, Bergstrom KSB, Vallance BA, Finlay BB. 2008. Chronic enteric Salmonella infection in mice leads to severe and persistent intestinal fibrosis. Gastroenterology. 134(3):768-80.