Vol.:(0123456789) 1 3 Arch Microbiol (2017) 199:881–890 DOI 10.1007/s00203-017-1362-5 ORIGINAL PAPER Efect of Anaerobiasis or Hypoxia on Pseudomonas aeruginosa Inhibition of Aspergillus fumigatus Bioflm Rajesh Anand 1,2,3  · Karl V. Clemons 1,2  · David A. Stevens 1,2   Received: 20 November 2016 / Revised: 26 February 2017 / Accepted: 8 March 2017 / Published online: 29 March 2017 © Springer-Verlag Berlin Heidelberg 2017 plug. These observations would explain why Pa becomes established in CF airways before Af, and why Af may per- sist during disease progression. Keywords Cystic fbrosis · Aspergillus · Pseudomonas · Intermicrobial inhibition · Anaerobiasis · Hypoxia Abbreviations Af Aspergillus fumigatus An Anaerobic Pa growth from nitrate-TSA plates AT Aerobic Pa growth from TSA plate ATn Aerobic Pa growth from TSA plate with nitrate BCF Pa bioflm culture fltrate CF Cystic fbrosis FB Af bioflm formation LC Live Pa cells n Number OD Optical density Pa Pseudomonas aeruginosa PB Preformed Af bioflm PCF Planktonic Pa culture fltrate PQS Pa quinolone signal TSA Trypticase Soy Agar XTT 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetra- zolium-5-carboxanilide inner salt Introduction Pseudomonas aeruginosa (Pa) and Aspergillus fumigatus (Af) are the most prominent bacterial and fungal patho- gens, respectively, in the airways of cystic fbrosis (CF) patients (Baxter et al. 2013; Coughlan et al. 2012; Folkes- son et al. 2012; Forsyth et al. 1988; Høiby et al. 2010; Mirković et al. 2016; Nicolai et al. 1990; Sabino et al. Abstract Pseudomonas aeruginosa (Pa) and Aspergillus fumigatus (Af) are the major bacterial and fungal pathogens in the airways of cystic fbrosis (CF) patients. This is likely related to their ability to form bioflms. Both microbes have been associated with CF disease progression. The inter- play between these two pathogens has been studied under aerobic conditions, though accumulating data indicates that much of the CF airway is hypoxic or anaerobic. We studied the microbial interaction in these latter environments. Pa is an aggressor against Af forming bioflm or as established Af bioflm, whether Pa is cultivated in aerobic, hypoxic, or anaerobic conditions, or tested in aerobic or hypoxic condi- tions. Pa cells are generally more efective than planktonic or bioflm culture fltrates. Pa growth is less in anaerobic conditions, and fltrates less efective after anaerobic or hypoxic growth, or against hypoxic Af. These, and other comparisons shown, indicate that Pa would be less efective in such environments, as would be the case in a CF mucus Communicated by Erko Stackebrandt. * David A. Stevens stevens@stanford.edu Rajesh Anand rajesh9in@gmail.com Karl V. Clemons clemons@cimr.org 1 California Institute for Medical Research, 2260 Clove Dr., San Jose, CA 95128, USA 2 Division of Infectious Disease and Geographic Medicine, Department of Medicine, School of Medicine, Stanford University, Stanford, CA 94305, USA 3 Present Address: Department of Biotechnology, Guru Ghasidas Vishwavidyalaya (A Central University), C.G., Bilaspur 495009, India