Friday, July 17, 2009

Ununbium gets a proper name

With IUPAC officially recognising discovery of element 112, a lot of news articles (such as this one) appeared hailing the “new element”. Of course, only the name copernicium (in honour of Nicolaus Copernicus) is new; the element was discovered in 1996 and was known as ununbium (Uub). The proposed symbol for this metal is Cp, probably not the best choice considering that Cp is widely used as a shorthand for cyclopentadienyl group — imagine we have enough copernicium to synthesise bis(cyclopentadienyl)copernicium, Cp2Cp! Fear not — according to WebElements,

as only a few atoms of element 112 have ever been made (through a nuclear reaction involving fusing a zinc atom with a lead atom) isolation of an observable quantity has never been achieved, and may well never be.

Monday, July 13, 2009

Iron trafficking as an antimicrobial target

The August issue of BioMetals contains proceedings of Symposium on Siderophores held at the ACS Meeting in Philadelphia, 2008. This mini-review caught my attention.

Readers of Biometals are aware of the special challenges posed by the need to acquire iron: an absolutely essential but highly insoluble metal in most biota, and a jealously protected one inside the human body. Microbial systems for Fe uptake and trafficking are consequently highly developed and fundamentally interesting. Limiting Fe under laboratory conditions can be detrimental or lethal, offering a means for limiting microbial growth. The potential for medicinally impeding Fe metabolism is a commonly, if sometimes uncritically, cited justification for in-depth biological studies of Fe acquisition. In fact, derailing the Fe supply train, while plausible as an antimicrobial strategy, is still largely untested in practice.

Since the iron acquisition mechanisms in microbes and higher eukaryotes are fundamentally different, it is possible to deprive the pathogen from iron without harming the host — for instance, by inhibiting the siderophore biosynthesis.