Metadata to collect while collecting plant associated microbial samples in the field

Another question for Twitter with some answers by Storify. Not I am putting in below the fold here so that the Storify emded only launches for those who want it to …
//storify.com/phylogenomics/metadata-to-collect-while-collecting-plant-associa.js[View the story “Metadata to collect while collecting plant associated microbial samples in the field” on Storify] In addition Russell Neches in my lab would like to add the following comments, which were too long for the comment option here.

The most important thing for interpreting -omic data is context. For
genomic data, this mostly means compare and contrast analysis against
other genomes, although there are other tools (GWAS-type studies,
ChIP-seq/chip, footprinting…). For metagenomes, comparisons against
other similar metagenomes can be of limited utility if the taxa
represented do not overlap very much.

The easiest thing would be to bring a smart phone and log GPS

coordinates and take wide and closeup photos, and make absolutely sure

that each one is explained in the field notes. This doesn’t necessarily
provide quantitative information, but it’s *REALLY* helpful to anyone

trying to analyze the data who wasn’t on the field mission. And it’s
cheap and easy.

For quantitative metadata, there are usually a number of abiotic
parameters that drive community structure, and many of these are
relatively easy to instrument. For example, pH, temperature and moisture
are very strongly correlated with community structure in terrestrial
soils. These parameters are very easy to measure. There are of course
other parameters that might be interesting; CO2, CO, CH4, C2H5OH, O2,
N2, nitrate, nitrite, phosphorous… but these are somewhat more
difficult to instrument at the moment, and (as far as I know) are
usually not as correlated with the very broad impact of pH, temperature
and moisture unless the system is near an extreme (e.g., the whole
system goes anaerobic, or metal-starvation in the open ocean).

However, while these parameters are easy to measure, they can also
fluctuate on time-scales that are relevant to microbial growth. As a
result, the temporal (and perhaps spacial) variation of these parameters
may be more important to the community structure than their “typical”
values. In way that is tends to frustrate field mission planning, it is
the temporal fluctuations *PRIOR* to sampling that are relevant.

There are two approaches : telemetry and local assistance. Telemetry
(“measurement from afar”) means placing instrumentation at the site that
has the ability to log or transmit data. Local assistance would vary
depending on the context of the site, but basically amounts to
partnering with someone who actually lives near the study site and
somehow convincing them to take measurements for you. Of course, the two
approaches are not mutually exclusive.

The simplest and probably best approach would be to partner with someone
near the study site who teaches fourth grade. Send them enough simple
gardener’s soil chemistry meters for their class (plus some extra for
the ones that inevitably get lost, disassembled or turned into
implements of mayhem and destruction).

For example, a quick search on Amazon turns up dozens of fairly
inexpensive gardening tools for measuring pH, moisture, temperature and
light intensity. Here’s one that looks like it might be useful :

http://www.amazon.com/Digital-Soil-Light-Tester-Plants/dp/B000RN23DM/

Here’s an even cheaper one that does pH, moisture and light, doesn’t
need a battery, and costs less than seven bucks :

http://www.amazon.com/Moisture-Meter-Light-Test-Function/dp/B007FMVOVK/

If you were asking a class of fourth graders to help gather metadata for
you, using instruments like these would cost perhaps $300, including
instruments, stationary, surveying flags, etc. Make that $500, and send
lots of extra stationary. Fourth grade classrooms never have enough
stationary.

Of course, if you’re going to ask people to do work for you, you must
treat them accordingly. Taking careful, regular measurements and writing
them down in a notebook is the bread-and-butter of science, and people
who do this work are called “scientists,” not “helpers.” There are
myriad implications to this, but one that I hope more people will
consider is sharing authorship. It is fair, it is honest, and it is
inexpensive.

The other option is telemetry. Thanks in no small part to the Arudino
project, this has gotten vastly easier and cheaper. At the cost of
learning a little bit about soldering and digital logic, you can wire up
virtually any sensor you like to a microcontroller, and then push that
data over a variety of communications platforms. There are Arduino
shields that interface with Ethernet, Wifi, Bluetooth, GSM, and even
satellite networks. Even a satellite uplink interface can be hacked
together for less than $200.

Of course, there are a lot of people interested in telemetry of various
sorts, and so you can find Arduino derivatives that have a lot of the
work done for you. For example, if you happen to want to want pH
telemetry, and your site happens to be within a few dozen meters of
someplace you can safely leave an old laptop, this product might
interest you :

http://www.sparkyswidgets.com/Products/Store/Details/tabid/81/ProductID/4/Default.aspx

Here’s another Arduino variant with an onboard FLASH logging interface,
solar/LiPo power management, a real time clock, a temperature sensor,
and interfaces for standard Arduino shields (e.g., a GSM shield), and an
interface for Xbee-style boards (e.g., bluetooth, Xbee, GPS, FM radio,
Wifi).

http://www.seeedstudio.com/wiki/Seeeduino_Stalker_v2.3

Attach sensors. Write software. Add battery and solar panel. Put into
watertight box. Deposit at field site.

Correcting for rRNA copy # in qPCR experiments

Asked this question on Twitter and thought I would share answers here via Storify.  I am putting it below the fold to allow people to avoid the Storify embed if they want to.
//storify.com/phylogenomics/correcting-for-rrna-copy-in-qpcr-data.js[View the story “Correcting for rRNA copy # in qPCR data” on Storify]

The books of science online 2013 #scio13

Took pics of the books on display at Science Online 2013.

Here they are

https://picasaweb.google.com/s/c/bin/slideshow.swf

Cool new paper from DeLong lab: Pattern and synchrony of gene expression among sympatric marine microbial populations

Definitely worth looking at this paper if you are interested in uncultured microbes: Pattern and synchrony of gene expression among sympatric marine microbial populations.  From Ed Delong and team, it is published under the “Open” pathway in PNAS.

Also see press release here: Scientists track ocean microbe populations in their natural habitat to …

Worth a read: The Sieve Hypothesis: Clever Study Suggests an Alternate Explanation for the Function of the Human Stomach | Guest Blog, Scientific American Blog Network

Quick post here pointing people to an interesting blog post by Rob Dunn: The Sieve Hypothesis: Clever Study Suggests an Alternate Explanation for the Function of the Human Stomach | Guest Blog, Scientific American Blog Network. Definitely worth checking out.

Finally back in the lab

After spending the majority of our time collecting samples and doing water chemistry on site, we are all back in our lab ready to do DNA extractions and PCR galore. Unfortunately, the kim wipes we used to scrub microbes off the walls of the tanks are too large to fit into our tubes with the extraction beads. After about an hour of stressing and improvising, we were able to get a usable amount of supernatant…or so we hope. We will find out after we do our PCR.

My progress with the Aquarium Project

Hello everybody, 

Thought I’d do a quick log/blog entry of what I have been doing in the lab for the past couple of days. I just got a brief introduction to sampling the first few times I was in the lab. I didn’t do too much of hands on sampling, but developed a fair idea of how it was done before it all ended.

And now we are moving on to do PCR’s and DNA extractions.  This is what I consider to be the core of the project and I truly hope to learn a great deal from it. I’ve never been exposed to all these techniques in this particular way and that makes it really exciting to learn all these things! I was really happy to see magnetic beads, cytometers and micro pipettes the first time I entered the Genome Center. 

The last time I was in the lab, I was introduced to the basics of analysis, and I learnt how to handle the micro-pipettes. I look forward to performing PCR this week.

Another important update: Currently, I am looking for people in the lab to work with me on the Undergraduate Research Conference. It is something I am really interested in because I love making posters and talking about research and also learning about research. If anyone is interested in doing this, I am willing to help out in any way possible.

The link to the conference page is here: http://undergraduateresearch.ucdavis.edu/urcConf/

I think it’s a good opportunity for the Eisen lab to talk about its achievements! 

If anyone is interested, please let David Coil know, and if you need help, please do ask me. I’d love to do my bit! I hope to hear back on this.

Water Chemistry Sampling: Our kit list

A couple of people have requested that I post information on the various kits and probes being used to assay water chemistry for our aquarium study.  Here’s the list, divided by type with a link to each item on Amazon.  Also various user complaints.

Probes:

pH  (worked fine, held calibration well)

Salinity (worked fine, held calibration well)

Temperature (annoying, a bit fiddly, I wouldn’t do this one again)

Titration-based kits:

Hardness, Alkalinity, Chloride, and Sulfide were all measured using this combo package  It also includes an iron assay that we didn’t use.  All of these kits are prone to error since they’re titration based.   But used very carefully (takes time!) they seemed to produce okay results.  I recommend using glass flasks instead of the plastic beakers supplied.

Colorimetric scanners:

Dissolved oxygen (this kit requires that you have a glass container capable of holding exactly 60 mls of water.. they don’t tell you this until you read the instructions.  Otherwise worked fine.  A bit hard to use but conversely you’ll learn new vocabulary from reading the instructions)

Ammonia (worked fine, but you have to be very careful to follow the instructions and mix between adding reagents or you’ll get a false high reading)

Nitrate (worked fine)

Nitrite (this one is pretty annoying; it’s hard to get the reagents into the tiny vial and these handheld meters turn themselves off after only 2 minute so if you get distracted you have to start over)

Phosphorus (see nitrite, but even worse.  As far as we can tell it’s not even possible to follow the instructions for this since it turns itself off before you finish mixing the reagents)

Preliminary chemistry data from Coral Pond #1

Since we’ve stopped sampling I went ahead and graphed out all the water chemistry data from Coral Pond #1.   Feeback, thoughts, comments etc. are welcome!

          Slide1

Slide2

Slide3 Slide4 Slide5 Slide6 Slide7 Slide8 Slide9 Slide10 Slide11

IBM will save the planet with this magical hydrogel – NOT

Well, press releases can drive me crazy.  And this one is one of the worst I have seen in a while: IBM News room – 2013-01-24 IBM and The Institute of Bioengineering and Nanotechnology Develop New Antimicrobial Hydrogel to Fight Superbugs and Drug-Resistant Biofilms – United States

This new fangled gel they have made they are very proud of.  That is good.  Pride in ones work is a good thing.  But getting the science wrong and making misleading statements is not.  Some statements I have issues with include

  • Able to colonize on almost any tissue or surface, microbial biofilms – which are adhesive groupings of diseased cells present in 80% of all infections – persist at various sites in the human body, especially in association with medical equipment and devices.
    • Huh?  Diseased cells?  What does this even mean?
  • When applied to contaminated surfaces, the hydrogel’s positive charge attracts all negatively charged microbial membranes, like powerful gravitation into a blackhole.
    • Again – huh?  How is this like gravitation in a black hole?
  • However, unlike most antibiotics and hydrogels, which target the internal machinery of bacteria to prevent replication, this hydrogel kills bacteria by membrane disruption, precluding the emergence of any resistance.
    • This is the killer statement.  They have apparently invented a treatment that no organism can resist.  It is therefore perfect.  Sort of like, well, penicillin?  Oh no, wait.  Sort of like chloroquine.  Oh no, wait.  I mean, sort of like streptomycin right?  Sorry – I meant tetracycline.  No no – I meant …. aaaaaaaaaaarrg.
I could go on.  Sounds like a possibly interesting new development.  But when you make absurd claims about it, and get the science all messed up, it does not give me that warm fuzzy feeling.  Annoyingly some news sources are basically just quoting from the PR with no skepticism.  For example, see this Daily Mail article. And this blip in The Star.  At least this in “The Conversation” has some comments on this being possibly overblown.  Anyway, shame on IBM for being more about hype than science.