Journal
MOLECULAR ORAL MICROBIOLOGY
Volume 36, Issue 3, Pages 214-224Publisher
WILEY
DOI: 10.1111/omi.12337
Keywords
dental caries; metal homeostasis; nutritional immunity; Streptococcus mutans; zinc
Categories
Funding
- National Institute of Dental and Craniofacial Research [DE019783]
Ask authors/readers for more resources
This study identified AdcABC as the major high affinity zinc importer of Streptococcus mutans and provided preliminary evidence that zinc is a growth-limiting factor within the dental biofilm.
Trace metals are essential to all domains of life but toxic when found at high concentrations. Although the importance of iron in host-pathogen interactions is firmly established, contemporary studies indicate that other trace metals, including manganese and zinc, are also critical to the infectious process. In this study, we sought to identify and characterize the zinc uptake system(s) of Streptococcus mutans, a keystone pathogen in dental caries and a causative agent of bacterial endocarditis. Different than other pathogenic bacteria, including several streptococci, that encode multiple zinc import systems, bioinformatic analysis indicated that the S. mutans core genome encodes a single, highly conserved, zinc importer commonly known as AdcABC. Inactivation of the genes coding for the metal-binding AdcA (Delta adcA) or both AdcC ATPase and AdcB permease (Delta adcCB) severely impaired the ability of S. mutans to grow under zinc-depleted conditions. Intracellular metal quantifications revealed that both mutants accumulated less zinc when grown in the presence of a subinhibitory concentration of a zinc-specific chelator. Notably, the Delta adcCB strain displayed a severe colonization defect in a rat oral infection model. Both Delta adc strains were hypersensitive to high concentrations of manganese, showed reduced peroxide tolerance, and formed less biofilm in sucrose-containing media when cultivated in the presence of the lowest amount of zinc that support their growth, but not when zinc was supplied in excess. Collectively, this study identifies AdcABC as the major high affinity zinc importer of S. mutans and provides preliminary evidence that zinc is a growth-limiting factor within the dental biofilm.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available