Oxygen Limitation , Antibiotic Tolerance , and Heterogeneous Gene 3 Expression 4 5 Running Title : S . aureus Agarose Gel Biofilm

1 Gel-entrapped Staphylococcus aureus as Models of Biofilm Infection Exhibit Growth in 2 Dense Aggregates, Oxygen Limitation, Antibiotic Tolerance, and Heterogeneous Gene 3 Expression 4 5 Running Title: S. aureus Agarose Gel Biofilm 6 7 Breana Pabst, Betsey Pitts, Ellen Lauchnor, and Philip S. Stewart 8 9 Center for Biofilm Engineering 10 366 EPS Building 11 Montana State University 12 Bozeman, MT 59717-3980 13 and 14 Department of Civil Engineering 15 Department of Chemical and Biological Engineering 16 (406) 994-1960 17 phil_s@biofilm.montana.edu 18 19 revised August 1, 2016 20 21 *Corresponding author 22 # Current address: Bozeman, MT 23 AAC Accepted Manuscript Posted Online 8 August 2016 Antimicrob. Agents Chemother. doi:10.1128/AAC.01336-16 Copyright © 2016, American Society for Microbiology. All Rights Reserved.