The curious case of Neisseria and the seven-carbon sugar

A scanning electron micrograph showing Neisseria gonorrheae bacteria (blue) infecting a type of human immune cell called a neutrophil (gold). (Image: Ryan Gaudet)
A scanning electron micrograph showing Neisseria gonorrhoeae bacteria (blue) infecting a type of human immune cell called a neutrophil (gold). (Image: Ryan Gaudet)

Walking into the little lunchroom in the back of the lab, I am greeted by a row of empty wine bottles. Celebratory drinks in the lab usually mean a manuscript’s been accepted for publication and when there’s that many empty bottles, you know it must be a pretty good journal. As I attempt to work out a wine to impact factor conversion in my head, the lab door opens and Ryan Gaudet (pronounced good-ie) walks in. Gaudet, a PhD student in the lab of Dr. Scott Gray-Owen at the University of Toronto, is the lead author of a paper recently published in the journal Science about a new signalling molecule produced by the bacteria Neisseria gonorrhoeae. It was for this paper that he and his labmates were celebrating.

To fully appreciate and understand this paper, we need to go back more than a decade to the early 2000s, when Adrienne Chen, an undergraduate student working in the Gray-Owen lab, noticed something peculiar: when cells infected with HIV were exposed to N. gonorrhoeae, HIV genes suddenly turned on and normally silent genes became expressed. This was a compelling finding because co-infection of HIV with the sexually transmitted infection gonorrhoea (caused by N. gonorrhoeae) is known to increase HIV shedding and enhance male-to-female transmission. A few years later, the mysteries of the gonorrhoea-HIV relationship drew Dr. Rebecca Malott, a postdoctoral fellow, to the Gray-Owen lab where she began a project aimed at trying to figure out how Neisseria bacteria turned on HIV gene expression.

That’s when the detective work began. Continue reading

Advertisements

Killer fat cells help protect against bacterial infections

Fat is bad. This is what doctors and nutritionists have preached for years, making fat public enemy number one in the battle against obesity. We now know that not all fat is bad. Unsaturated fats, like those found in fish and nuts, have many potential health benefits while saturated and trans fats should be avoided. For the first time, researchers have shown how fat cells in our skin can directly help protect against a bacterial infection.  Continue reading