Glucose deprivation induced upregulation of phosphoenolpyruvate carboxykinase modulates virulence in Leishmania donovani.
Various physiological stimuli trigger the conversion of noninfective Leishmania donovani promastigotes to the infective form. Here, we present the first evidence of the effect of glucose starvation, on virulence and survival of these parasites. Glucose starvation resulted in a decrease in metabolically active parasites and their proliferation. However, this was reversed by supplementation of gluconeogenic amino acids. Glucose starvation induced metacyclogenesis and enhanced virulence through protein kinase A regulatory subunit (LdPKAR1) mediated autophagy. Glucose starvation driven oxidative stress upregulated the antioxidant machinery, culminating in increased infectivity and greater parasitic load in primary macrophages. Interestingly, phosphoenolpyruvate carboxykinase (LdPEPCK), a gluconeogenic enzyme, exhibited the highest activity under glucose starvation to regulate growth of L. donovani by alternatively utilising amino acids. Deletion of LdPEPCK (Δpepck) decreased virulent traits and parasitic load in primary macrophages but increased autophagosome formation in the mutant parasites. Furthermore, Δpepck parasites failed to activate the Pentose Phosphate Pathway shunt, abrogating NADPH/NADP+homoeostasis, conferring increased susceptibility towards oxidants following glucose starvation. In conclusion, this study showed that L. donovani undertakes metabolic rearrangements via gluconeogenesis under glucose starvation for acquiring virulence and its survival in the hostile environment.
Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Hajipur, Bihar, India.|Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Savita
S
Saini
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Ayan
A
Kumar Ghosh
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Ruby
R
Singh
Department of Microbiology, All India Institute of Medical Sciences, Patna, Bihar, India.
Sushmita
S
Das
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Kumar
K
Abhishek
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Ajay
A
Kumar
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Sudha
S
Verma
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Abhishek
A
Mandal
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Abul
A
Hasan Sardar
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Bidyut
B
Purkait
Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Ashish
A
Kumar
Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Hajipur, Bihar, India.
Kislay
K
Kumar Sinha
Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Hajipur, Bihar, India.|Division of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Indian Council of Medical Research, Patna, Bihar, India.
Pradeep
P
Das
D001343:Autophagy; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D005943:Gluconeogenesis / Q000235:genetics / Q000502:physiology; D005947:Glucose / Q000378:metabolism; D007893:Leishmania donovani / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism*; D008264:Macrophages / Q000469:parasitology; D018384:Oxidative Stress; D010728:Phosphoenolpyruvate / Q000378:metabolism; D010730:Phosphoenolpyruvate Carboxylase / Q000235:genetics / Q000378:metabolism*; D013217:Starvation / Q000378:metabolism; D015533:Transcriptional Activation; D015854:Up-Regulation; D014774:Virulence; D037521:Virulence Factors / Q000378:metabolism
D037521:Virulence Factors; D010728:Phosphoenolpyruvate; D017868:Cyclic AMP-Dependent Protein Kinases; D010730:Phosphoenolpyruvate Carboxylase; D005947:Glucose