Acute Sensitivity of V. cholerae to Phosphate Starvation: A Possible Case of Futile Metabolism

• Published in: Current microbiology Vol. 79; no. 2; p. 38
• Main Authors: Paranjape, Shridhar, Shashidhar, R.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-02-2022; Springer Nature B.V
• Subjects: Artificial seawater; ATP; Biomedical and Life Sciences; Biotechnology; Carbon; Cell death; E coli; Escherichia coli; Growth conditions; Growth media; Life Sciences; Metabolism; Microbiology; NADH; Nicotinamide adenine dinucleotide; Nitrogen; Nutrient sources; Nutrients; Phosphate; Phosphate starvation response; Phosphates; Redox potential; Seawater; Sensitivity; Starvation; Stringent response; Survival; Vibrio; Vibrio cholerae
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-021-02726-z

Multi-nutrient starvation profiles are emerging as an essential feature of human pathogen studies. In the present work, we attempted to understand why
V. cholerae
cannot survive in the growth media that includes carbon and nitrogen but lacks phosphate. However, it can survive starvation in artificial seawater without all three major nutrients (carbon, nitrogen, and phosphate).
V. cholerae
survival was critically affected below ten mM of phosphate content in the media. Interestingly, the survival of the bacteria in low phosphate conditions improved when cultured under sub-optimal growth conditions, sub-optimal C: N ratio, non-metabolizable nutrient sources, and activation of stringent response. The phosphate starved cells had low ATP levels and high NADH levels; A quick drop in ATP, coupled with impaired redox potential, may lead to cell death. We also observed the acute sensitivity to phosphate limitation among the other members of the genus
Vibrio
. Among those,
V. vulnificus
and
V. cholerae
showed the highest sensitivity (< 0.1%). Among the members of γ-proteobacteria,
E. coli
and
C. sakazaki
and
S.
Typhimurium showed the lowest sensitivity (10%), and the
A. hydrophila
and
V. harvey
showing intermediate (1 – 2%) survival in low phosphate condition. The presence of carbon and nitrogen in the media over-weigh the information about the lack of phosphate that would cause continued but futile metabolism. The current study shows a general lack of coordination between carbon, nitrogen, and phosphate metabolism in
V. cholerae
.