Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Ferric iron reduction by Cryptococcus neoformans

K J Nyhus1, A T Wilborn, E S Jacobson

  • 1Department of Internal Medicine, Virginia Commonwealth University, Richmond 23298-0049, USA.

Infection and Immunity
|February 1, 1997
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

3-Hydroxyanthranilate in Cryptococcus neoformans: a secreted reductant that does not enable wood rot.

Medical mycology·2003
Same author

Pathogenic roles for fungal melanins.

Clinical microbiology reviews·2000
Same author

Genetic and physiologic characterization of ferric/cupric reductase constitutive mutants of Cryptococcus neoformans.

Infection and immunity·1999
Same author

Ferrous iron uptake in Cryptococcus neoformans.

Infection and immunity·1998
Same author

Redox buffering by melanin and Fe(II) in Cryptococcus neoformans.

Journal of bacteriology·1997
Same author

Discordant regulation of phenoloxidase and capsular polysaccharide in Cryptococcus neoformans.

Journal of medical and veterinary mycology : bi-monthly publication of the International Society for Human and Animal Mycology·1996
Same journal

The cholesterol-dependent cytolysin promotes <i>Streptococcus</i> systemic spread and induces arachidonic acid accumulation-mediated lethality in a murine intraperitoneal infection model.

Infection and immunity·2026
Same journal

Phenotypic and genotypic analysis of <i>Candida albicans</i> vaginal isolates reveals that <i>ECE1</i> expression underpins pathogenicity.

Infection and immunity·2026
Same journal

<i>Staphylococcus aureus</i> pore-forming toxins differentially shape disease severity in experimental endophthalmitis.

Infection and immunity·2026
Same journal

Group B streptococcal membrane vesicles induce proinflammatory responses in neonatal meninges.

Infection and immunity·2026
Same journal

<i>Pseudomonas aeruginosa</i> infection causes lysosomal dysfunction in the cystic fibrosis bronchial epithelium.

Infection and immunity·2026
Same journal

The role of probiotics in restoring and maintaining vaginal microbiome health: a review.

Infection and immunity·2026
See all related articles

Cryptococcus neoformans utilizes secreted 3-hydroxyanthranilic acid (3HAA) and melanin to reduce Fe(III) for uptake, with iron-depleted cells showing higher reduction activity. This highlights key mechanisms for iron acquisition in pathogenic fungi.

Area of Science:

  • Microbiology
  • Mycology
  • Biochemistry

Background:

  • Pathogenic yeast Cryptococcus neoformans requires iron for growth and survival.
  • Iron acquisition in C. neoformans is essential and involves the reduction of extracellular Fe(III) to Fe(II) prior to cellular uptake.
  • Understanding these iron reduction mechanisms is crucial for developing targeted antifungal strategies.

Purpose of the Study:

  • To investigate the mechanisms employed by Cryptococcus neoformans for the reduction of Fe(III) to Fe(II).
  • To identify and quantify the specific reductants involved in this process.
  • To determine the influence of iron availability and cell growth phase on iron reduction.

Main Methods:

  • Utilized the chromogenic ferrous chelator bathophenanthroline disulfonate to measure Fe(III) reduction.

Related Experiment Videos

  • Compared iron reduction rates between iron-depleted and iron-replete cells.
  • Analyzed secreted compounds in cell supernatants, including 3-hydroxyanthranilic acid (3HAA).
  • Assessed the reducing activity of melanized versus non-melanized cells.
  • Main Results:

    • Iron-depleted C. neoformans cells exhibited significantly higher Fe(III) reduction rates (57 nmol/10^6 cells/h) compared to iron-replete cells (8 nmol/10^6 cells/h).
    • Secreted 3-hydroxyanthranilic acid (3HAA) was identified as a major Fe(III) reductant, with concentrations correlating positively with iron reduction activity.
    • Melanized stationary-phase cells demonstrated a 16-fold higher Fe(III) reduction rate than non-melanized cells, suggesting melanin's role in iron reduction.

    Conclusions:

    • Cryptococcus neoformans employs multiple mechanisms for Fe(III) reduction, including secreted compounds like 3HAA and the redox polymer melanin.
    • Iron availability and cell growth phase dynamically regulate these iron reduction pathways.
    • These findings provide insights into the fungal iron assimilation process and potential therapeutic targets.