Trehalose 6-phosphate phosphatase is required for cell wall integrity and fungal virulence but not trehalose biosynthesis in the human fungal pathogen Aspergillus fumigatus.
The trehalose biosynthesis pathway is critical for virulence in human and plant fungal pathogens. In this study, we tested the hypothesis that trehalose 6-phosphate phosphatase (T6PP) is required for Aspergillus fumigatus virulence. A mutant of the A. fumigatus T6PP, OrlA, displayed severe morphological defects related to asexual reproduction when grown on glucose (1%) minimal media. These defects could be rescued by addition of osmotic stabilizers, reduction in incubation temperature or increase in glucose levels (> 4%). Subsequent examination of the mutant with cell wall perturbing agents revealed a link between cell wall biosynthesis and trehalose 6-phosphate (T6P) levels. As expected, high levels of T6P accumulated in the absence of OrlA resulting in depletion of free inorganic phosphate and inhibition of hexokinase activity. Surprisingly, trehalose production persisted in the absence of OrlA. Further analyses revealed that A. fumigatus contains two trehalose phosphorylases that may be responsible for trehalose production in the absence of OrlA. Despite a normal growth rate under in vitro growth conditions, the orlA mutant was virtually avirulent in two distinct murine models of invasive pulmonary aspergillosis. Our results suggest that further study of this pathway will lead to new insights into regulation of fungal cell wall biosynthesis and virulence.
Puttikamonkul
Srisombat
S
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Willger
Sven D
SD
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Grahl
Nora
N
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Perfect
John R
JR
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Movahed
Navid
N
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Bothner
Brian
B
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Park
Steven
S
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Paderu
Padmaja
P
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Perlin
David S
DS
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
Cramer
Robert A
RA
Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59718, USA.Department of Medicine, Duke University Medical Center, Durham, NC 27713, USA.Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USA.Public Health Research Institute, International Center for Public Health, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA.
D000818:Animals; D001232:Aspergillus fumigatus / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D004195:Disease Models, Animal; D055744:Invasive Pulmonary Aspergillosis / Q000382:microbiology / Q000473:pathology; D008168:Lung / Q000473:pathology; D051379:Mice; D009154:Mutation; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D016019:Survival Analysis; D014199:Trehalose / Q000378:metabolism*; D014774:Virulence
D003470:Culture Media; D014199:Trehalose; C023178:trehalose-phosphatase; D010744:Phosphoric Monoester Hydrolases