Author Archives: jennomics

About jennomics

I am a Postdoc in Jonathan Eisen's Lab at UC Davis. jennomics@gmail.com

If you were at Lake Arrowhead, you should know the MBL

Posted on by
2

The recent Lake Arrowhead Microbial Genomics Conference (#LAMG12) was the first time I’ve been reunited with one of my classmates, Ben Tully, (@phantomBugs) from the MBL. (In June 2009, I spent 6 weeks at the Microbial Diversity Course at the Marine Biological Laboratory in Woods Hole.) On several occasions, we explained to people at the conference how we met, and were met with blank stares.

Just as Laura Sauder (@LauraASauder) forgave the medical microbiology folks in the room for not recognizing a photo of Sergei Winogradsky, I am willing to do the same for those who do not recognize the Microbial Diversity course at the MBL. But, if your flavor of microbiology has anything to do with the words environment, community, genomics, metagenomics, evolution, or ecology, then you should fall into one of three categories: 1) You went to the course. 2) You are going to the course. 3) You want to go to the course.

Here is some text from the course website:

Students will isolate, cultivate, and experiment with characteristic microbial types from various marine, freshwater and terrestrial habitats, including those microbes living symbiotically with animals and plants. Emphasis will be on the isolation and cultivation of organisms that are distinguished by their phylogenetic, physiological, and morphological properties. Techniques for cultivation of strict anaerobes and phototrophs will be emphasized. Examples of microbial types that will be isolated are methanogens, acetogens, sulfate-reducing anaerobes, fermentative anaerobes and both oxygenic and anoxygenic phototrophs, as well as bacteria involved in the geochemical cycling of various metals. Magnetic bacteria, sulfur-oxidizing bacteria, spirochetes, and luminescent bacteria will also be studied. A laboratory component on molecular approaches to microbial diversity will instruct students to use approaches of molecular phylogeny and comparative genomics. This will involve isolation and amplification of 16S rRNA genes as phylogenetic markers and the use of computer software programs to analyze nucleic acid sequences and to construct phylogenetic trees. As the capstone activity of the course, participants will conduct an individual research project of their own design.

You will learn a LOT about microbes and how they do what they do. You will become a microbiologist. The way you view the world will be permanently altered. Just ask anyone who has attended the course. But, what that blurb does not tell you is that every day, you sit through lectures or talks by the world’s expert on a given subject. Time to learn about thermophiles? Here is Karl Stetter. And, not only will he talk to you in the classroom about his research, he will stick around for a few days. He will hang out in the lab, eat meals with you, and he will be part of the crowd that makes the trek to the secret beach when the bar closes.

It’s just a really, really special place, and if you were at Lake Arrowhead, if you were at ASM, if you were at ISME, (I know there are more, but you get the idea) you must fall into one of those three categories.

More MBL posts to come…

Mechanical Turk

Posted on by
Reply

Yesterday morning, my last day at the Lake Arrowhead Microbial Genomics Conference, I saw a tweet from Holly Bik (@Dr_Bik) about a talk she was attending at a Phenomics conference about the sociology of Amazon’s Mechanical Turk Web Service. What is Mechanical Turk, you may ask? Well, what’s really funny is that just minutes before I had answered that question for Ben Tully (@phantomBugs) in describing how I used it to help with my dissertation research.

Mechanical Turk allows you to crowd source little tasks that are easy for humans, but not computers. For example, if you need to write a short caption for 1000 photos at about 1 minute per photo, that would take you about 2 full days of work. Or, you can upload those photos to Mechanical Turk, along with some instructions about how to write each caption. Each photo becomes a little job, sent out to all the workers on Mechanical Turk. You offer to pay $.03 per job, and then you sit back with a glass of wine and watch the World Series of Poker. Some hours later, all of your work is done, and you did none of it. Sure, you are out $30, but hopefully your time is worth more than $15/day.

You are provided with the worker ID for each job. You can spot-check each worker’s work and if you do not like it, you can reject all of their work, do not pay them, and then those photos go back into the work queue

So, how did I use this for my dissertation research? I wanted to look at environmental correlates of horizontal gene transfer (HGT). HGT is the exchange of DNA between different species, and it is fairly common among microbes. One potentially important mechanism of DNA transfer is the uptake by a cell of DNA that is floating about freely in the environment (transformation). If the environment is inhospitable to the DNA molecule, then the probability of transfer by transformation should be quite low. For example, and in particular, I wanted to ask whether organisms that live in very low pH environments experience a lower incidence of HGT.

I can predict the incidence of HGT for an organism directly from the genome sequence, so all I need is to find out at what pH that organism grows. That should be straightforward because every time a genome is submitted to a public database, the submitter will include all of the associated environmental data (or metadata) that is available, and since that submitter grew the organism in culture in the laboratory, he or she must know at which pH it best grows. Right?

Now, because I am who I am, I want to do this analysis in a phylogenetic context, using some Phylogenetic Comparative Method (I should talk about this more in another post.) In particular, I opted to use Felsenstein’s Independent Contrast method as implemented in Phylocom. I built a reference phylogeny for ~800 bacteria and archaea which have genome sequences available (this part is currently in revision) and then I “looked up” the optimum growth pH for each of them. This look up process should be straightforward, too, because the data are submitted to a searchable database, like at NCBI or the JGI’s IMG. Right?

Well, nothing that should be straightforward ever is in my academic life. I was able to get the pH data from the IMG by grabbing all of the webages with the metadata on them and parsing them with a little perl script. But when I did that, I only got pH data for ~100 of the ~800 organisms in my reference phylogeny. For any given organism, if I spent a couple of minutes poking around in the literature, I could easily find the optimum growth pH, so it’s not like it’s not out there. But, I couldn’t automate the “poking around” process, and after spending two full days of work, I had only retrieved pH data for about 200 additional organisms. Because I was down to the wire in terms of a dissertation submission deadline, and because I consider my time fairly valuable, I just couldn’t bring myself to keep at it.

I was complaining vociferously about those ~600 people who couldn’t be bothered to spend their couple of minutes to include pH data with their genome submissions. Russell Neches (@ryneches), who seemed to really get a kick out of my uncharacteristic vociferousness, suggested that Mechanical Turk might work for me.

I created a job (called a HIT): “Given the name of an organism, report it’s optimum growth pH”

My job looked like this:

In retrospect, maybe I could have come up with some better instructions, but I think for most things, these should work. I paid $.08 per job, so I spent $40. I rejected a lot of work because I got answers like: 37.5 or comments like “I couldn’t find it.” There was one worker who commented, “This was a cool HIT.” And that worker did a lot of jobs and seemed to do good work. I focused my spot-checking on values at the extremes, since most things live at a neutral pH.

But, here’s what I found: If you follow the first approach that I suggest and google the organism name+optimum+pH+growth, sometimes, you would see something that looked right in the google search results, but was actually referring to enzyme activity rather than growth conditions.

I can tell that this is not the information I’m looking for, but I don’t really expect a Mechanical Turk worker to be so discerning, especially not for $.08. There were a few other common errors that I think it would have been difficult to avoid, even with more clear instructions. I could have submitted some of the jobs in duplicate so that I could check the workers against each other, but I suspect that this type of mistake would be made by anyone without a fair degree of specialized knowledge on the subject (who is not likely to be doing this sort of work.)

So, in the end, I ended up spending a lot of time double-checking the results. I don’t know if I saved any time by doing it this way, but it was FUN! I will definitely keep it in the back of my mind, and hope to be able to use it again someday!

Catch-up

Posted on by
2

UPDATE: After I wrote the post below, I stopped posting to this blog for several years. During that time, I got married, converted to Judaism (although it still feels weird to call myself a Jew, mostly because my husband is not so observant – he did not ask me to convert, by the way –  and I am agnostic), had a baby, finished my PhD, and started working as a Project Scientist in Jonathan Eisen’s lab. Most of my previous posts were about hiking and a road trip that I took from Davis to Durham to attend a workshop on Phyloinformatics at NESCent. During that road trip, I stopped along the way to collect Drosophila because I thought that the Drosophila-microbiome interaction was going to be the main focus of my dissertation research. One of my strokes of genius was to solicit the help of big-name Drosophila biologists at regular intervals along the way to help me out. I asked them to take me collecting with them when I got to their town. My plan was to camp all the way from Davis to Durham and back. Without fail, everyone I contacted either offered to take me out collecting, put me up for the night, spent an entire day with me, identifying and sorting species in their lab, or all of the above. It was an awesome experience that I really should write a book about.

Anyway, I’ve finished the PhD and feel like this new chapter in my life should be accompanied by a renewed dedication to this blog. So here we are.

 

Post proper:

I’ve been a slacker about this, so I’m going to try to slowly catch up to the present. On my way home from Angel Island in April, my car hit a milestone. Here it is:

I didn’t know at the time, but this marks the beginning of the era in my car’s life in which most everything falls apart. I guess you could think of it as a time for a re-commitment to my car. Time to re-invest the purchase price.

Buying a 1992 used VW Cabriolet: $2000.
Keeping the car running for the next 100,000 miles: well over $2000 (I’m afraid to add it all up.)
Getting out of Davis whenever I want to: priceless

Angel Island

Posted on by
Reply

Angel Island is in the middle of the San Francisco Bay. Last Saturday, with a pretty big group of people (most of whom I had never met,) I took the ferry from Tiburon to go hiking there. It was a really spectacular day for the bay, which is frequently foggy and cold. We hiked around and up to the highest peak (~1500ft). All along the hike, you’re treated with views of the north and east bay (Mount Tamalpais, Oakland/Berkely Hills, even Mount Diablo) and the city (San Francisco.) Click on the link to see some pictures from the hike.

Leaving Tiburon on the ferry
Aproaching Angel Island


View of the dock
a wild iris

view of Mt. Tamalpais (but we just say “Mount Tam”)
at the top of Mt. Livermore, we stop for lunch and take in the view of the Golden Gate Bridge

more GG Bridge.

It was a little hazy, which makes the pictures not turn out so great,
but it was really a spectacular day!

these flowers were everywhere

typical California coastline (on a very small scale!)
this rock crusher was used to produce gravel for the roads on the island

you can ride your bike all the way around the island on these roads

one of many nice views

just thought this looked cool


after the hike we relaxed with beers in this outdoor seating area while we waited for the ferry
jellyfish!

leaving Angel Island

seagull in Tiburon

We had dinner at Guayamas. The food was pretty good, but the company was better.

More hiking?

Posted on by
54


Yep! I think I’ll be doing lots of hiking this summer. Yesterday, I hiked to the top of Mt. St. Helena (pronounced hell-EEN-uh for those not from around here.) I was worried about this hike because I thought I would be too much of a wuss to handle it, but as it’s the day after and I’m still walking around (and most importantly, my knees didn’t hurt yesterday!) I must be tougher than I thought. It was 10 miles, about 2100′ elevation gain.

Hey, it’s Napa Valley!


Views like this all the way up.
Yep, like this.
View from the top. Only a single cloud in the sky.

Manzanita
I was diggin the Manzanita. It’s red.
Like good Californians, we went wine tasting after the hike.
I didn’t like the wine, but I liked this sign.

Oregon

Posted on by
Reply


So that I don’t always have to hike alone and so I can make some friends who are not ten years younger than me, I decided to join this Meetup group. My first adventure with the group was a 4-day trip to Eugene, Oregon to do some hiking. We stayed at a hostel and did some very scenic local hikes. It was kinda chilly and rained a little, but it was so much fun – and beautiful! Fortunately, the people I carpooled up there with were really nice and funny (as was everyone else!) and very knowledgeable about the terrain we were driving though. Hopefully, I’ve made some new friends.

The first hike we went on was to Sweet Creek Falls.
This was a short easy hike along a river that had fall after fall after fall, culminating in this one.



There was snow on the ground and it was chilly, but not too bad, and it rained for most of the hike, but it was light. It was very lush and green.



Then we drove to the coast to see the Heceta Head Lighthouse. It was really beautiful. Not so much the lighthouse, which was cute, but the coast was pretty spectacular.



Chris, the Meetup organizer, had contacted the Eugene Hiking Meetup group organizer, Mark, so we could all hike together. Only Mark came out to hike with us, but he was awesome. He drove us around in this old ambulance that had been converted into a 20-passenger van. And he brought his dog Bonkers, on whom I must admit I have a huge crush!

Sleepy Bonkers
The Vanbulance

The final hike of the day was at Enchanted Valley. It was kinda weird and boggy.

Some Enchantment

The next day, we split up and my group went to the Willamette National Forest. The trail was muddy and at times a little steep, so I felt like I was finally getting a little exercise.


At one point, the boys started hauling ass ahead of us, but they were kind enough to leave a giant arrow on the ground at a fork for us. I thought it was pretty cool.


I split off from the rest of the group so that I could try out my new little pen fishing rod. It took some practice, getting it to cast and reel in smoothly. I didn’t get a bite, but I found a big elk antler down by the water, so I got a nice trophy!

Fishin’ Hole

On the way home, we stopped at Table Mountain for a little walk through the wildflowers. It was a really neat place that I hope to come back and explore sometime.



My carpool friends:

Paul

Steve
Liz

Zim Zim Falls

Posted on by
1

The weather has been really nice here, and I’m inspired to get outside more frequently. Also, I think I’m kinda bored. School/work keeps me really busy, and I really enjoy it, but I definitely don’t want my life to be so one-dimensional. So a couple of weekends ago, I decided to go on a hike somewhere pretty close by. Somehow, I came across this hike to Zim Zim Falls and it seemed perfect because it was only about an hour away, it was an easy 4ish-mile hike, and the drive there was scenic. Oh, and a waterfall!

Here are some pictures from the drive there.

Putah Creek

Lake Berryessa

Putah Creek

This creek just flows right over the road.


To get to Zim Zim Falls, I had to cross Zim Zim Creek several times. My feet got wet, but I was prepared for that.

There are signs of hunters everywhere. I ran into a guy who told me that in a month, when turkey season opens, you’ll be hiking along and run into a guy with a gun slung over his shoulder. I’d be worried about getting shot, so I’m glad I made it up there when I did.

I made a wrong turn and ended up hiking straight up the side of a hill. In the picture below, you can see the creek running through a bald spot in the valley below (that’s where I was supposed to stay) and at the bottom of the picture, you can see the steep trail I was climbing. I climbed straight up for about an hour. I kept thinking that the falls must be just ahead. I thought that I could hear the water, but it was just the wind in the trees. (I know, for someone so smart…)

See how far away the valley floor is now (below)? Now I’m hiking along the top of this ridge.

There were lots of pretty flowers, and at this point, my mood was good enough that I stopped to take some pictures of them.

Then, I saw this:

Can you spot the waterfall? There’s a little white smudge against a dark circular patch of rock. Now, I was bummed. It’s way over on the other side of the valley. Nevertheless, I hiked all the way over there because I was going to eat my lunch at the base of the falls, dammit! I ate lunch at around 6pm.
I’ve gotta figure out how to turn these pictures around. Anyway, here we are at the base of the falls.
I’ve got to work on my self-portraiture skills, too.

WABDA

Posted on by
2

I recently learned about this new NIH initiative to crack down on “brain-doping” in academic researchers. The idea is that if scientists use brain-enhancing (I prefer mental-capacity-enhancing, or mental-creativity-enhancing, or MCE) drugs, it is analogous to athletes using physical performance-enhancing drugs like steroids. So, in the competition for funding, the MCE drug users would be at an unfair advantage.

While I honestly do not know anyone who takes MCE drugs, I must admit that if I did, I would be asking for the hook-up! I believe that the NIH should actually be obligated to prioritize funding for scientists who are willing to risk the (mild!) side effects of MCE drugs in order to produce top-notch scientific results. If I were running a big funding agency, I might well REQUIRE all of the PIs/post-docs/grad students whose salaries were being paid with my grant money to sign a contract outlining their commitment to taking MCE drugs on a regular basis for the duration of the grant. Although some evidence suggests that MCE drugs cause a drastic reduction in the length of a young academician’s career, post-docs and grad students are cheap labor and easily replaced. Really, if you can get one year of high productivity out of a grad student or post-doc via the use of MCE drugs, then you are going to be way ahead of the curve.

I think that the true tragedy of this emerging anti-MCE drug policy is that the researchers who are both law-abiding AND the most enthusiastic about and committed to the advancement of science will be forced to rely solely on the archaic (but legal) substances that we currently associate with increased mental performance: primarily coffee, but also beer and/or wine. The diuretic effects of both caffeine and alcohol serve to frequently distract many young scientists from the task at hand, arguing further for the benefit of using “next-generation” brain-doping substances.

What’s the downside, really? We quickly come up with a cure for cancer? Someone figures out how to grow corn on Mars to power our cars? I say, give me the drugs!