In the spring of 2012, Connecticut College chemistry professor Marc Zimmer was an instructor on the University of Virginia's Semester at Sea onboard study abroad program. As a leading specialist on the forefront of research into green fluorescent proteins (GFP) - glowing jellyfish proteins that are genetically reproduced, infused into laboratory animals, and utilized in more than 3,000,000 medical and biological experiments tracking disease - Zimmer hit on the idea of focusing his course on a different indigenous malady relative to each port of call during the voyage.

Stops included Ghana (with a malaria problem); Manaus, Brazil (the tropical parasitic disease Chagas); Cape Town, South Africa (HIV/AIDS); and Hong Kong and Shanghai (cancer).

"Two things stand out about that experience," says Zimmer, a native of South Africa with a boyish smile and a gregarious nature. "We did field trips at some of those ports where students saw actual people who were sick and suffering - and that really hit home with them. Suddenly, it wasn't abstract and we weren't talking theory."

On a lighter note, Zimmer explains that there were about 500 students onboard a ship with one physician, and they reported ongoing hypochondriacal elements and imagined maladies.

“The doctor came to me and said, 'I think I've worked this out. I'll tell you what port you were just in based on the symptoms the students think they have,'" he says.

Zimmer's latest book, "Illuminating Disease - An Introduction to Green Fluorescent Proteins," just out from the Oxford University Press, was inspired by the Semester at Sea trip and is based on his class notes from the trip. Zimmer's previous book, "Glowing Genes" (2005, Prometheus Books), was an early history of scientific exploration in GFP.

"I first heard about GFP several years ago when (a molecular biologist named) Doug Prather, who first proposed using GFP as a tracer molecule, spoke at Conn," Zimmer says. "At the end of the talk, he said, 'And this is where we are - this is the part we don't understand, and it's going to be very important.' And I thought, 'I can do this.'"

Within a few months of compiling data, Zimmer was able to conduct an experiment and correctly predict the outcome.

"Once you've done that," he says, "there's momentum to keep going. It's like catching a big wave before anyone else rides it."

After the publication of "Glowing Genes," Zimmer's reputation continued to grow.

In 2008, for example, the Nobel committee was considering awarding the Chemistry Prize to Osamu Shimomura, Martin Chalfie and Roger Y. Tsien, the scientists who had been hand-selected by Prather to carry on his work in the development of GFP as a diagnostic means.

In doing their homework on the award, the Nobel committee made a phone call.

"I had a message at 8 a.m.," Zimmer recalls. "There was a guy with a thick Swedish accent, and he said he was with the Nobel Selection Committee. I know the field pretty well -well enough to know they weren't going to give ME the award - but I still thought someone was joking."

Nope. Zimmer was flown to Stockholm, where he answered a variety of background questions on GFP and the pioneering chemists - "They wanted facts and context, not my opinion," he says - and then Zimmer and his wife returned to Sweden for the actual ceremonies when, in fact, Shimomura, Chalfie and Tsien won the award.

"It was probably the most amazing experience in my life," Zimmer says. "Just the entrance of the award winners was astonishing. And it's a bit humbling because they actually show the Nobel ceremonies live in Sweden and Japan. It's that big a deal in some places in the world."

Since then, Zimmer's own research and experimentation have continued in dramatic fashion - providing him with the background and knowledge to write the new book. And while "Glowing Genes" certainly worked as a popular science book as well as a textbook, Zimmer consciously wanted "Illuminating Disease" to appeal to a mainstream audience as well as scholars.

"I told my agent I definitely wanted to go with a trade press - someone like Little, Brown or Penguin," Zimmer says. "We tried for about a year and it was a bit of a hard sell, so my agent suggested we go with a university press that has trade aspects. Oxford was the first to respond, and they're an excellent house. The manuscript ended up being a little more academic than I wanted, but it's certainly written with a crossover audience in mind."

Written in pleasant and conversational style, "Illuminating Disease" starts off with a concise and up-to-the-minute history of green fluorescent proteins and the scientists who have been integral to the work. Then, chapter by chapter, using anecdotes, case studies and lavish and colorful illustrations, Zimmer walks the reader through various diseases and explains the way GFP tracking and testing is becoming a Day-Glo highway of possibilities for treatment and possible cures.

Consider the representative chapter on mosquito-borne dengue fever, for example. According to the World Health Organization, dengue fever is the fastest spreading vector-borne viral disease with epidemic potential on earth - 20 times more common than the flu - and there's no vaccination for it.

Zimmer describes the strategy, taking place in Florida, of using millions of genetically altered fluorescent mosquitoes. When they mate with wild mosquitoes, the subsequent larvae glow and are incapable of living to mate or bite. Scientists can not only track the insects but, ultimately, the mosquito populations will subside.

"For the scientist, this is a background story," Zimmer says. "At the same time, I think the general public isn't as aware of science beyond subjects like global warming. What I hope to do with the book is to get people talking. The more we talk, the more we learn. And maybe the layperson says, 'Wow, there's so much more we can do.'"

Zimmer pauses, reflecting.

"What's happening with GFP is that we can suddenly see what's happening inside living organisms. That's huge. To me, in the context of science, this is like the invention of the microscope."

r.koster@theday.com

Twitter: @rickkoster

IF YOU GO

Who: Author Marc Zimmer

What: Connecticut College chemistry professor discusses his book "Illuminating Disease, An Introduction to Green Fluorescent Proteins"

When: 5 p.m. Saturday

Where: La Grua Center, 32 Water St., Stonington

How much: $5

For more information: (860) 535-2300