PASADENA, Calif.If one is good, two can sometimes be better. Researchers at the California Institute of Technology (Caltech) have certainly found this to be the case when it comes to a small HIV-fighting protein.
The protein, called cyanovirin-N (CV-N), is produced by a type of blue-green algae and has gained attention for its ability to ward off several diseases caused by viruses, including HIV and influenza. Now Caltech researchers have found that a relatively simple engineering technique can boost the protein's battling prowess.
"By linking two cyanovirins, we were able to make significantly more potent HIV-fighting molecules," says Jennifer Keeffe, a staff scientist at Caltech and first author of a new paper describing the study in the Proceedings of the National Academy of Sciences (PNAS). "One of our linked molecules was 18 times more effective at preventing infection than the naturally occurring, single protein."
The team's linked pairs, or dimers, were able to neutralize all 33 subtypes of HIV that they were tested against. The researchers also found the most successful dimer to be similar or more potent than seven well-studied anti-HIV antibodies that are known to be broadly neutralizing.
CV-N binds well to certain carbohydrates, such as the kind found in high quantities connected to the proteins on the envelope that surrounds the HIV virus. Once attached, CV-N prevents a virus from infecting cells, although the mechanism by which it accomplishes this is not well understood.
What is known is that each CV-N protein has two binding sites where it can bind to a carbohydrate and that both sites are needed to neutralize HIV.
Once the Caltech researchers had linked two CV-Ns together, they wanted to know if the enhanced ability of their engineered dimers to ward off HIV was related to the availability of additional binding sites. So they engineered another version of the dimersthis time with one o
|Contact: Deborah Williams-Hedges|
California Institute of Technology