The MER blog has as its mandate to provide a place to discuss the latest trends in the field. To that end, I have started a series of interviews that will focus on women who have earned the respect of their colleagues and who constitute leaders in their scientific field. The first of these distinguished women is Rosie Redfield.
Rosie Redfield is a Professor at the University of British Columbia in Vancouver Canada. Her research sits at the interface of bacterial molecular genetics, microbial evolution, and the evolution of sex. After completing a Ph.D. at Stanford University under Allan Campbell, she did a two-part postdoc; a year with Richard Lewontin at Harvard University and two years with Ham Smith, a 1978 Nobel Laureate, at Johns Hopkins University. In 1990 she took up a faculty position at University of British Columbia and has been there since. Most notable for her ideas on natural competence and quorum-sensing in bacteria, recently she was at the centre of a media maelstorm for her criticism of a paper by Wolfe-Simon et al. 2010. In this article published in Science, Wolfe-Simon and colleagues asserted that bacteria found in Lake Mono in California were able to substitute arsenate for phosphate in their nucleic acids and proteins. Redfield, however, argued in a detailed post on her blog, RRResearch, that there was no convincing evidence that arsenic had been incorporated into the DNA. This criticism drew worldwide attention and propelled into the public’s awareness a new understanding of how the bloggosphere has changed the methodology of scientific evaluation and communication.
Here is Part 1 of our telephone interview.
Me: Describe a little bit about your background and journey to your current position as a scientist.
Rosie: I began my PhD in a biology lab at Stanford doing tissue culturing experiments very similar to the work I had done in my Masters. After a year and a half, I decided I was in the wrong lab, and switched to Allan Campbell’s lab – although his lab was much smaller, I had been impressed by the great questions he asked in seminars. His lab worked on E. coli and bacteriophage lambda. I found that I really liked working on microbes because it is so easy to learn from your mistakes. In my PhD work I regularly did a badly designed experiment one day but was able to do it right the next day.
I wasn’t initially particularly interested in evolution but I used the travel allowance of my Canadian MRC Studentship to go to the Darwin Centenary Conference in Cambridge, England (100 years after his death). It was full of luminaries in evolutionary biology and their talks changed my perception of what were interesting problems. I came away convinced that I should do my post-doc work on the molecular biology underlying the evolution of sex. At another meeting a few years later I had a conversation with Dan Hartl, who suggested that I work on natural competence (why bacteria take up DNA). I had never really thought about natural competence so I went home, patched up my ignorance, and decided that that this was indeed an open niche for evolutionary investigation. And today I still work on natural competence.
Me: Would you say that your biggest contribution to science then is the solution to the problem of natural competence.
Rosie: The whole ‘What’s your biggest contribution/’ is a complicated question. Contributions are as much in the eye of the beholder as in the eye of the person who has done the science. If your work is never recognized as a contribution then it doesn’t matter how good the science was, it wasn’t a contribution.
I think that the question of why bacteria take up DNA is very important, and I think I’ve found the correct answer, but most microbiologists don’t even actually think that this is an interesting question. Knowing why bacteria take up DNA is really important for the whole field of the evolution of because if I’m right and bacteria take up DNA for food, then there is nothing in bacteria that natural selection has acted on that promotes true recombination. And that means whatever the reason for why eukaryotic sex exists, it solves a problem that bacteria don’t have.
I think my ideas of quorum sensing have also been an important contribution, even though I’ve never had any grants for this or done any experiments. I proposed that bacteria haven’t evolved auto-inducers as a way to talk to each other, but that secretion and sensing of autoinducers is simply a diffusion-based way for bacteria to sense the properties of their microenvironments. This hypothesis is now widely mentioned (if not accepted), and a number of published experiments support my ideas.
Me: Why have you never worked on quorum-sensing the way you work on natural competence?
Rosie: We haven’t done any work on quorum-sensing because the basic idea doesn’t need any experiments. The experiments illustrate what is possible but they don’t prove how natural selection has acted. Both ‘Why do bacteria take up DNA?’ and ‘Why do bacteria produce quorum-sensing chemicals?’ are questions fundamentally about how natural selection has acted. For quorum-sensing much of the evidence was already available, it was the interpretation that differed. And the experiments that others have done since then were quite sophisticated, requiring specialized skills and tools I don’t want to become expert in. With natural competence, my lab’s molecular biology and microbiology skills could generate much of the needed evidence on how regulation works, how the decisions are made, what kinds of processes have evolved, and this information would guide our thinking about how natural selection has acted.
Me: How and why do you persist in the face of other ignoring your work?
Rosie: It’s because I really do think that my hypotheses about natural competence and quorum-sensing are well supported by both experimental and theoretical evidence. But it’s like being an atheist in a room full of Christians. Most scientists learned long ago (freshman biology?) that recombination is good because it generates genetic variation, and they’re not prepared to question this now, after a career built on this assumption. When you say to them or write, here’s an argument that weakens your position, what they do is quickly look for a simple counter-argument without giving it any critical evaluation. (“Your hypothesis must be wrong because of this factoid.”) I don’t blame them (not much anyway), because this is what we all do when someone tries to poke a hole in ideas that we’re committed to.
Me: What do you think are the most important questions in your scientific field?
Rosie: The problem with this question is that I don’t really have ‘a field’. I work at the intersection of bacterial genetics, molecular biology, microbial evolution, and the evolution of sex. For transformation as a field I think the most interesting question is how does the DNA get across the membranes? For the evolution of sex – do bacteria have sex in the sense of true recombination? For evolutionary processes in bacteria – is there anything like a species? For some bacteria there probably is and for some bacteria probably not.
More generally, the big challenge for microbiology now is understanding the real lives of bacteria in their natural environments. This is extremely difficult, as we can’t watch them (they’re too tiny) or detect how their microenvironment changes (we lack sensors at that scale) or see what they do (the action is all at the molecular and biochemical level). Instead we study the behavior of massive populations growing in ridiculously unnatural laboratory cultures.
Me: How do you get new ideas that you want to then pursue with experiments?
Rosie: Most of the things that I think of as really good ideas, the ones that have changed the direction of my research, have come in a flash (a eureka! moment) when my brain puts together ideas whose collective implications I didn’t previously see. My brain is good at that – putting things together and saying, wait if this is true, that can’t be true. Unfortunately it’s not something I can turn on at will.
Me: Is this because you are widely read?
Rosie: Well, in part. I am widely read, because partly I’m a word junkie and partly because I’m curious about so many things. I’m also very distractible so I spend a lot of time doing stuff that’s not directly relevant to my specific area of research (or to whatever task I should be focusing on at the moment). But in the long term this is valuable because I’m able to see the bigger picture and the bigger issues. This lets me put ideas together in a way that other people haven’t. And it’s this breadth and connection-making that has created my novel research niche at the interface of multiple fields. I think a lot of grad students are afraid to take the risk of thinking and reading broadly. They worry that if they don’t know everything about one small area then they’ll be seen as ignorant and they’ll never get a job. But in fact, breadth can also be a road to success.
Me: Recently your blog has drawn worldwide attention for your critical assessment of the Wolfe-Simon et al 2010 paper, but you have been blogging since 2006. You describe in your first post that the purpose of your blog is “to give me a semi-public place to describe the ongoing process of doing and thinking about my lab’s research. ” What draws you to participate in Open Notebook Science?
Rosie: It’s partly because I want the public to be able to see what scientific research looks like. I like the idea of a random person clicking around (say, using Blogger’s ‘Next blog’ link) and landing on my research blog. At least sometimes, they’d read enough to realize that this is a scientist writing about doing research, and they’d leave with a slightly better understanding of the process of science.
My other reason for writing a research blog is that openness fosters good science. That is, I believe that the more openly we do science the better the science is going to be. One example of the benefits of open science that we now take for granted comes from back in the 1970s. When the very first DNA sequences were being determined, the National Library of Medicine made a decision to set up what became Genbank, and journals made the decision to require that authors who published DNA sequences had to deposit this data in GenBank, where other people could have access to it free of charge. This was a pivotal decision, but they could just as easily have decided that sequences should be treated as confidential information so the researchers who generated them get all the benefits. This decision to be open was responsible for all of the research that used these sequences and all of the genetic resources we have today.
Redfield R. 2009. Looking to bacteria for clues. Science. 325(5943): 946
Redfield, R. J. 2001. Do bacteria have sex? Nature Reviews Genetics 2:634-9.
Redfield, R. J. 2002. Is quorum sensing a side effect of diffusion sensing? Trends in Microbiology 10:365-370.
Redfield, R. J. 1994. Male mutation rates and the cost of sex for females. Nature 369: 145-147.