Michael Thomas Tiedemann
Biography
Michael Tiedemann was born in Sudbury, Ontario. He attended LoEllen Park S.S. and finished high school in 2003. Michael is currently on the UWO Fencing Team and fences Epee. He also enjoys squash, mountain biking and staying late in the lab.
Graduate Degree(2007-present)
Currently a TA for Inorganic Chemistry 271a and Chemistry 024b
Michael is currently working on heme transport in Staphylococcus aureus.
Staphylococcus aureus, an antibiotic resistant bacterium, is becoming a
substantial problem in hospitals and communities worldwide. It is responsible for
numerous deaths. Infections caused by Staphylococcus aureus can range from superficial
wound lesions to more severe infections such as pneumonia, osteomyelitis and
bacteremia(1). Treatment for Staphylococcus aureus is costly and can still result in
patient death due to the bacteria’s growing resistance to antibiotics such as methicillin.
Staphylococcus aureus is now known as a superbug.
Bacterial survival is largely dependant on iron scavenging. An important host
defense mechanism involves sequestering iron in transport and storage proteins such as
hemoglobin or ferritin. Staphylococcus aureus has adopted specialized mechanisms for
scavenging iron from the host and is largely successful via specialized iron scavenging
pathways. The recently identified cell wall and membrane-associated iron regulated
surface determinant (Isd) proteins is one such pathway. The Isd proteins allow the
bacterium to scavenge iron from the heme in hemoglobin. There are several Isd proteins
located at different depths in the cell wall and membrane (IsdA, IsdB, IsdC, IsdE and
IsdF). However, little is known about the overall scavenging mechanism, which may
serve as a route for killing the bacteria.
The ultimate goal of Staphylococcus aureus research is to understand how the
bacterium scavenges iron and from this knowledge find a cure or exploit a weakness and
kill it without using antibiotics. Through the use of molecular modeling,
electrospray ionization mass spectroscopy and mutation of the amino acids that facilitate
heme binding, a mechanism of heme transport in Staphylococcus aureus will be
determined so that a “large” picture of how this bacterium functions is created. This may
lead to identification of a possible weakness in this mechanism and subsequently,
exploiting this weakness in Staphylococcus aureus will kill the bacterium.
(1) Tenover, F.C., and Gorwitz, R. J. (2006) in Gram-positive pathogens (Fischetti, V.A., Novick, R. P., Ferretti,
J. J., Portnoy, D.A., and Rood, J.I., Eds.) pp 526-534, ASM Press, Washington, DC.
Undergraduate Degree (2003-2007)
H.B.Sc. Specialization in Chemistry with a Minor in Advanced Chemistry from the University of Western Ontario
Undergraduate Thesis: Radical Cleavage of Monolayers for Patterning using Scanning Electrochemical Microscopy (SECM) (Supervised by Dr. Mark Workentin and Dr. Zhifeng Ding)
