Chaperonin point mutation enhances cadmium endurance in Saccharomyces cerevisiae

Biotechnol Lett. 2021 Sep;43(9):1735-1745. doi: 10.1007/s10529-021-03151-9. Epub 2021 May 28.

Abstract

Objective: To study the effect of the mutation in conserved G412E in Cct7p subunit of CCT complex on its cellular fate.

Results: TriC/CCT is a dynamic multimeric protein that assists in protein folding in an energy-dependent manner. A point mutation in the ATP binding pocket in the equatorial domain of the Cct7p subunit delays the doubling time. The cell size was twice the wild type, and the formation of protein aggregates suggests disturbed folding of the proteins. Upon growing in stressful conditions of arsenous acid and cadmium chloride, the mutant was lethal in As3+ but grew well in Cd2+ with 10.5 µg cadmium uptake mg-1 compared to the wild type. The increased expression of vacuole transporters YCF1 and BPT1 by ten-fold and two-fold in mutant indicates the metal transportation to the vacuole.

Conclusion: CCT complex was vulnerable to the mutation in G412E in the Cct7p subunit of protein folding molecular machinery. Interestingly, already stressed cells provided robustness against oxidative stress and cadmium sequestration in the vacuole.

Keywords: BPT1; Cadmium; Protein aggregation; TriC/CCT; Vacuole sequestration; YCF1.

MeSH terms

  • ATP-Binding Cassette Transporters / genetics*
  • Arsenites / pharmacology
  • Arsenites / therapeutic use
  • Arsenites / toxicity
  • Cadmium Chloride / pharmacology*
  • Chaperonins / chemistry
  • Chaperonins / genetics*
  • Gene Expression Profiling
  • Gene Expression Regulation, Fungal / drug effects
  • Microbial Viability / drug effects
  • Models, Molecular
  • Point Mutation*
  • Protein Conformation
  • Protein Folding
  • Saccharomyces cerevisiae / drug effects
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development*
  • Saccharomyces cerevisiae Proteins / genetics*

Substances

  • ATP-Binding Cassette Transporters
  • Arsenites
  • Saccharomyces cerevisiae Proteins
  • YCF1 protein, S cerevisiae
  • arsenous acid
  • Chaperonins
  • Cadmium Chloride