SD-CAB Researcher Spotlight - Susan Golden, Ph.D.

By Amanda Herman

Susan Golden is a member of the Faculty of 1000 Biology, a Fellow of the American Academy of Microbiology, and a Member of the National Academy of Sciences. In addition, she runs a lab at UCSD that studies circadian rhythms of gene expression in cyanobacteria. Golden summarizes her graduate school and postdoc experiences, how cyanobacteria are useful in the production of biofuels and how SD-CAB has shaped the direction of her research in this month’s SD-CAB Researcher Spotlight.

How did you decide that studying cyanobacteria was your passion?

I grew into it. I started working on cyanobacteria as a grad student. I wanted a "recombinant DNA" project, and when I started grad school in 1978, such approaches were still new and not used in most labs. I had a chance to join a lab in which the PI (Lou Sherman) had just done a sabbatical to learn basic molecular cloning methods with the idea of capitalizing on the then-recent discovery of a transformable cyanobacterium. My job was to develop a cloning system for that species, Anacystis nidulans R2, now known as Synechococcus elongatus PCC 7942, with the idea of using it to discover new genes involved in photosynthesis. Later I chose to do my postdoc in Bob Haselkorn's lab not so much because he worked on cyanobacteria, but because he was researching transcriptional regulation. I had expected to change organisms and research directions, but when I got there I still had "one last thing" I wanted to do from a loose end of my PhD work, and I ended up finding interesting new directions with S. elongatus. Thus, I just continued my PhD work on through my postdoc and into my independent research lab. The areas of emphasis and technologies have changed over the years, but I'm still working on my favorite little bug, the Anacystis that I was among the first to work with genetically. Being at the right place at the right time is my forte. I literally walked into Sherman's lab, while he was on sabbatical, within seconds of his postdoc writing (snail mail back then) to Lou: don't overlook the contribution a graduate student could make to this project.

How do cyanobacteria fit in with the production of biofuels?

Initially cyanobacteria were dismissed as biofuel organisms because they don't naturally store carbon as neutral lipids (oil droplets) that are easily converted to biodiesel. However, cyanobacteria are easier to genetically modify than are eukaryotic algae, and they can be engineered to make designer chemicals. Many species have growth advantages as crops: filamentous forms that are easy to harvest, some fix nitrogen, and they can grow at high pH conditions that kill off a lot of invading or grazing pests. Moreover, new biomass conversion technologies are making it possible to get useful hydrocarbons from biomass without requiring neutral lipids as a starting point. Thus, cyanobacteria can contribute in many ways to the enterprise.

What advice would you give to students interested in pursing research in academia?

Do it only if you love it. The challenge is that you have to constantly raise money just to do your job (to fund your lab), and many people end up depending on you to provide their salaries. That's a lot of pressure. However, it is fantastic to have the freedom to choose what to study (within reason), and to see the transformation that occurs in a student from the time he or she enters the lab to when they leave (as a scientist!).

What do you like to do in your spare time?

I like to read good novels. I'm open to a lot of genres, but they really need to be well written, with good character development and good use of language.


If you could have one famous scientist over for dinner (living or deceased), who would it be?

I think George Washington Carver would be a fascinating dinner companion.


How has SD-CAB helped further the success of your laboratory?

Being part of SD-CAB has swept me into applied microbiology and alliances with biotech companies. I'm learning a lot, and doing more as part of the group than I would have done on my own. I'm engaging in collaborations that I wouldn't have assembled on my own. The activities and interactions, and the growing reputation of SD-CAB around the world, are all good for my research program and for forcing me to expand my scientific horizons.

Amanda Herman is Ph.D. candidate at UCSD and a volunteer writer and outreach coordinator with SD-CAB. You can contact her at abherman@ucsd.edu.

Biologists Use Algae-Produced Protein in Global Health Initiative

A research team in the Division of Biological Sciences headed by Stephen Mayfield will produce a mammary gland protein called MAA from algae to determine if has the potential to significantly reduce infectious diarrheal diseases, a major cause of infant mortality in the developing world.

The UC San Diego biologists will supply their algae-produced MAA to researchers at the University of Nebraska Medical Center as part of a newly funded initiative from the Bill & Melinda Gates Foundation to enable researchers worldwide to test unorthodox ideas that address persistent health and development challenges.

Mayfield, a professor of biology and director of the San Diego Center for Algae Biotechnology, is also one of the founders of Sapphire Energy, a San Diego company known for its development of a crude oil replacement produced from algae.

Mayfield’s research team engineered edible algae to produce high levels of bovine colostrum MAA using Sapphire Energy’s algae biotechnology platform. The MAA will be used by researchers at Nebraska headed by Thomas McDonald, a professor of pathology and microbiology there. His team of scientists has demonstrated that the protein increases the production of a natural protective barrier in the intestine against organisms such as Salmonella that can cause diarrhea.

For more on the research project and the grant received by the research team go to: http://app1.unmc.edu/publicaffairs/todaysite/sitefiles/today_full.cfm?match=8735

Algae Industry Magazine Interviews Dr. Stephen Mayfield

Algae Industry Magazine recently interviewed Dr. Stephen Mayfield about the EDGE Initiative, a 4 million dollar project that prepares the future workers of the bioenergy sector through certificate classes and hands-on industry internships. In this article, Dr. Mayfield describes the origins of EDGE, what the green work force looks like, how some of San Diego’s local biotechs and nonprofits contribute to the training process, and what the future holds for the program. Check out the full story here. Stay tuned in the next few weeks for exciting blog entries from EDGE participants who recently completed internships this past summer!

Sapphire Energy

by Amanda Herman

Tim Zenk, VP of Corporate 
Affairs at Sapphire Energy

Sapphire Energy is a local biotech with a bold mission statement:  “To change the world by developing a domestic, renewable source of energy that benefits the environment and hastens America’s energy independence.”  While all startup companies boast unique visions and lofty expectations in paragraph form, only a small number actually meet their goals in real time, and Sapphire is undoubtedly a gem among these few (pun intended).  It was established in 2007 with only a handful of employees and an ambitious desire to manufacture direct replacement fuels for the current gasoline, diesel, and jet distillates.  Since then it has grown exponentially, with a work force of over 100 and facilities in San Diego, Orange County, and Las Cruces and Columbus, New Mexico.  After talking with Tim Zenk, the Vice President of Corporate Affairs at Sapphire, it is clear that this burgeoning company is well on its way to solving the nation’s most pressing energy issues today for a greener tomorrow.  Read on for my short question and answer session with Zenk to learn more about Sapphire.

Q:  Why is there a necessity for a company like Sapphire?

Sapphire's planned Algae Plant 

A:  Sapphire Energy was founded based on the concept that there had to be a better way to do biofuels.  There had to be (1) a biological source of materials that could be converted into hydrocarbons (organic compounds naturally found in crude oil), (2) these biological materials needed to be easily scalable in accordance with a growing demand, and (3) have no impact on existing agriculture.  Sapphire applies viable technology in a sustainable manner.  The use of algae-based oils eliminates the need for additional transportation and refining systems in addition to reducing greenhouse gas emissions.  Algae are also one of the most scalable things on the planet, so large-scale production (over 1 billion gallons a year) is a feasible goal.

Q:  How is the green crude produced by Sapphire different from the biodiesel fuel made by other companies?

Mills at the outdoor 
field station

Sapphire manufactures renewable crude oil from algae, using a proprietary procedure of converting direct sunlight and carbon dioxide to generate high-value hydrocarbons.  Green crude produced in this manner uses the same industrial, refining, and distribution methods as the existing petroleum infrastructure and can be used as a drop-in fuel replacement.  This makes it a superior alternative to companies that use algae to make biofuels, which are not compatible with the same industrial refining processes.

One Barrel For Baja

Kristian Gustavson (right) and 
Nathan Schoepp (left

by Amanda Herman

The Biology Field Station at the University of California San Diego (UCSD) is home to a thriving center for cutting-edge experiments made possible by the San Diego Center for Algal Biotechnology (SD-CAB) in support of research aimed towards understanding and developing eco-friendly energy solutions, like the 1 Barrel for Baja (1BFB) project.  1BFB is a student-based undertaking, which started and quickly gained momentum based on scientific collaborations between laboratories at UCSD, the Salk Institute, the Scripps Institution of Oceanography (SIO), and San Diego State University with funding from the US Department of Energy and local private industries.  Kristian Gustavson is a former Master’s student from Dr. Jim Leichter’s Laboratory at SIO.  He is the visionary behind the 1BFB initiative, and continues volunteering at the Field Station to further the progress of the project.  Gustavson, along with Nathan Schoepp, a Chemistry graduate student in Dr. Michael Burkart’s Laboratory at UCSD and five undergraduate volunteers from the Biofuels Action and Awareness Network (BAAN) helped construct the greenhouse and the wet laboratory.  Both facilities function as factories for growing algae and are rapidly expanding to accommodate the demands of the 1BFB endeavor.

The greenhouse contains large bags 
of algae in various stages of growth.

Algae are a broad and diverse group of organisms that make complex organic compounds. They grow significantly faster than conventional food crops such as maize and soybeans.  They also thrive in warm, arid, and salty climates, making them an attractive alternative to other crop-based biofuels and the greater San Diego area a prime location for their cultivation.  Schoepp summarizes the process of taking algae from the greenhouse to the barrel: first, large bags that hold 50 to 100 liters of freshwater algae are inoculated with one of three algal production strains that have been specially engineered for better growth.  A continuous supply of both air and CO2 is pumped through the bags for four days.  After this incubation period, the algae are harvested and their biomass, the biological material containing important fuel precursor molecules, is isolated by centrifugation.  The biomass is then sent to Dr. Skip Pomeroy’s Laboratory at UCSD, where the lipids and fats and are extracted and further converted into usable diesel fuel.

Gustavson’s goal is to obtain enough biomass to fill one 42-gallon barrel with biofuel (also known as B100 biodiesel).  In an effort to scale up the production by the end of the summer, Gustavson and Schoepp plan to grow 300 to 500 liter algal cultures in large plastic pools of saline water.  They hope to eventually build an in-ground circulating pond where bulk volumes of algae can be cultured.  Optimizing the growth of one algal strain and promoting its use as a renewable form of energy to local companies is the next step for Gustavson. “This is a good opportunity for UCSD to lead the way in applied algal biotechnology,” he says.  The Baja 1000 is a series of off-road desert races that will take place on November 17^th, 2011 in the Baja California Peninsula.  The race is sanctioned by SCORE International and often showcases new technologies in motor vehicles.  Gustavson will race one of three diesel enduro motorcycles from Holland using the fuel that he and his team have produced from start to finish.

The success of the One Barrel for Baja project has also been made possible with the help of Drs. Steve Mayfield, Greg Mitchell, Michael Burkhart, Skip Pomeroy, and Dominick Mendola. 

Amanda Herman is Ph.D. candidate at UCSD and a volunteer writer and outreach coordinator with SD-CAB. You can contact her at abherman@ucsd.edu.