[ad#PhycoBiosciences AIM Interview]

Innovations

Mosquitoes from the genus Anopheles transmit the protozoan that causes malaria.

Mosquitoes from the genus Anopheles transmit the protozoan that causes malaria.

On Developing an Algal-based Cure for Malaria

June 17, 2012, by Dr. Stephen Mayfield
AlgaeIndustryMagazine.com

Over the past ten years, work from our lab has identified mechanisms of chloroplast gene expression that have allowed for development of recombinant protein expression and metabolic engineering in the algal chloroplast.

Transformation of algae is relatively easy. You can transform either the nuclear or the chloroplast genome. If you get DNA in, and you have a good selectable marker and a good selection system, you can get transformation.

There are rather complex structures that fold into three-dimensional RNA elements that are bound by protein factors, and that is a requirement for translation. We still haven’t sorted this all out, but we’ve identified a number of elements that are required, and a number of proteins that interact in order to get translation.

Having accumulated these proteins and showing that they were bioactive, we went back to ask, “What’s the advantage of expressing something inside of a chloroplast, or inside of an algae? What biological advantages does that give you over expressing the protein in a bacterial or a mammalian cell culture?”

So one of the things that the lab came up with was to try and express malarial proteins. And the reason we wanted to express these was because malarial proteins have many different domains inside of them, folded in very complex proteins. Malaria is a euchariotic parasite, and their proteins form complex structures that have many disulfite bonds, but the proteins are not glycosolated.

That’s important because when you try to express these proteins in bacterial systems, they are incapable of doing the complex fold and they won’t form disulfate bonds. If you’re trying to express these in mammalian systems, they’ll form the disulfite bonds and correctly fold them, but then they decorate the proteins with sugar—they glycosolate them—so that if you use these as a vaccine, you end up getting antibodies to the sugars rather than the proteins.

Mayfield Lab team (L to R): Javier Gimpel, Dan Barrera, Liz Specht, Beth Rasala, Jamie Gregory, Stephen Mayfield, Carla Jones, Mike Hannon, Trang Le, Miller Tran, Julie Kim, Crystal Warning

Mayfield Lab team (L to R): Javier Gimpel, Dan Barrera, Liz Specht, Beth Rasala, Jamie Gregory, Stephen Mayfield, Carla Jones, Mike Hannon, Trang Le, Miller Tran, Julie Kim, Crystal Warning

So, we knew that inside of chloroplasts—inside of all plastids—we could fold complex proteins. We could make disulfate bonds. But we also knew there was no mechanism to glycosolate these. So we expressed three different surface antigens, PFS-25, 28 and 45. All of those proteins accumulate very well inside the chloroplast. Importantly, they all fold correctly. So then, antibodies directed against native proteins, which only recognize the correctly folded native proteins, also recognized the algal-expressed proteins.

Most importantly, when we injected these proteins into mice, the mice-generated antibodies recognized the correctly folded proteins, and we had an immune response. Those antibodies blocked malaria transmission within the mice.

It’s important to understand, for something like malaria, that most recombinant vaccines today cost about a hundred dollars a dose, and generally you need two or three injections. So clearly for the people in the malaria belt—and there are about two billion people on this planet in the malaria belt—they simply do not have the resources to even think about spending two or three hundred dollars for a vaccine.

I think these developments using algal proteins are beginning to give us the opportunity to make those vaccines cheap enough that we can think about the real possibility of inoculating two billion people.

A co-founder of the San Diego Center for Algae Biotechnology (SD-CAB), and Sapphire Energy, Dr. Mayfield is Professor of Molecular Biology, and the John Dove Isaacs Chair of Natural Philosophy, at UC San Diego.

More Like This…

Go to HOME Page

Copyright ©2010-2012 AlgaeIndustryMagazine.com. All rights reserved. Permission required to reprint this article in its entirety. Must include copyright statement and live hyperlinks. Contact editorial@algaeindustrymagazine.com. A.I.M. accepts unsolicited manuscripts for consideration, and takes no responsibility for the validity of claims made in submitted editorial.

From The A.I.M. Archives

— Refresh Page for More Choices
On September 25, 2014, a photobioreactor for the cultivation of algae was officially unveiled during a seminar at Thomas More University College in Mechelen, Belgium. Und...
Cyanobacteria, also known as blue-green algae because of their color, have endured for more than 2.5 billion years, providing ample time to adapt to changes in the Earth'...
Allan Koay writes in thestar.com about a Universiti Malaya research project paving the way for the commercial production of paper pulp and bioethanol from seaweed. The Al...
Kailua Kona, Hawaii-based Cyanotech has announced financial results for the third quarter and first nine months of fiscal year 2015, ended December 31, 2014. For the thir...
Kevin Valine at the Modesto Bee writes that the California city of Modesto may sell the algae that grows in its roughly 1,000 acres of sewer ponds at its Jennings Road wa...
Sebastian Rich reports on PBS Newshour about the Central African Republic city of Bangui, which has been caught in the crossfire between warring Muslim and Christian grou...
Scientists from the J. Craig Venter Institute (JCVI), a not-for-profit genomic research organization in La Jolla, California, have published a paper outlining new synthet...
In Japan, the Algae Biomass Energy System Development Research Center, headed by Professor Makoto Watanabe, was established at the University of Tsukuba on July 1. The ne...
Dr. Gloria Naa Dzama Addico and Kweku Amoako Atta deGraft-Johnson write in Graphic Online about the plight of the fisher folks in Ghana — in the throes of depleting fish ...
Sarah Zhang writes in Wired Magazine that the single-cell green algae Chlamydomonas reinhardtii have an eyespot that makes use of light-sensitive proteins. One of them is...
Ewen Callaway writes in the jounal Nature that restrictions on harvests and exports of Gelidium seaweed in Morocco have affected the global supply of the lab reagent agar...
Algatechnologies Ltd. has launched its AstaPure® 5% Natural Astaxanthin oleoresin, derived from Haematococcus pluvialis microalgae. This latest addition to the AstaPure f...