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Clinical Microbiology: Open Access | ISSN: 2327-5073 | Volume: 7
Microbiology: Education, R&D and Market
7
th
Annual Summit on
September 28-29, 2018 | San Antonio, USA
Molecular mechanisms governing heme regulation of Jumonji C domain-containing proteins in yeasts
Li Zhang
The University of Texas, USA
H
eme, iron protoporphyrin IX, is a crucial metallonutrient and a major source of iron for living organisms ranging from bacteria
to humans. In humans, 95% of functional iron is in the form of heme. Heme is a central molecule in oxygen metabolism and
utilization. It serves as a prosthetic group or cofactor for many proteins and enzymes involved in oxygen utilization and metabolism.
The utilization of heme as an iron source strongly influences the virulence of most pathogenic bacteria and some pathogenic fungi.
For example,
Candida albicans
secrets a hemolytic factor and uses heme and hemoglobin as an iron source.
Cryptococcus neoformans
can subsist on solely heme- and hemoglobin-sourced iron. Further,
Histoplasma capsulatum
can only utilize iron in the form of heme.
Consequently, disrupting heme uptake may be a viable approach to inhibit fungal infection. Additionally, understanding how heme
acts to control various cellular processes should provide novel insights into how pathogenic fungi can be suppressed. Particularly, our
lab has extensively investigated the molecular mechanisms underlying heme regulation of two yeast regulators, the heme activator
protein Hap1 and the heme activator protein Hap1 and multi-functional regulator Gis1. Gis1 is a yeast orthologue of the KDM4/
JMJD2 subfamily of proteins containing a Jumonji C (JmjC) domain, which functions as an
α
-ketoglutarate (AKG) and Fe(II)-
dependent histone demethylase. Heme directly binds to Gis1 and promotes transcriptional and demethylase activities of Gis1. The
molecular mechanism by which heme promotes Gis1 activities will be discussed.
li.zhang@utdallas.eduClin Microbiol 2018, Volume: 7
DOI: 10.4172/2327-5073-C3-040