Geomicrobiology Lab

The microbiology lab is closely associated with the organic geochemistry lab, and Dr. Lenczewski oversees both.

A very significant fraction of the living things on earth cannot be seen with the naked eye, and these micro-organisms are the objects of interest in this lab. Microbes can serve two very useful research purposes, as remediators and as indicators. As remediators, some have been found that can use a contaminant ( oil, for instance ) as food, and thereby destroy it. As indicators, they have much to say about the health of an ecosystem, or, viewed another way, how changing use patterns, pollution, or the like, may be affecting it. This can be of particular interest in cases where pesticides are involved, but it is also very useful to establish what "normal," or unstressed, ecosystems look like.

Noe Velazquez and part of the microbiology lab

In conducting such research, the important thing is to be able to identify the micro-organisms present, and there are two possible ways of doing it. One is to make a "culture" of them and identify them by observing what sorts of things they prefer for food, what sorts of things they excrete, and what sort of living conditions ( e.g. temperature, light or the absence of it, etc. ) encourage their growth. It develops that only a small fraction of the microbes which may be of interest in an ecosystem can be identified in this way, however, and so it becomes necessary to identify them on the basis of their DNA signatures. This is what the microbiology lab is designed to do, isolate and replicate microbial DNA.

The picture shows a part of the lab, with undergraduate student Noe Velazquez using an automatic pipette to charge a sample block. The white objects in front of him and in the near background are part of the apparatus used to study microbial DNA. The lab is equipped to do two different procedures. One, (pictured here) reveals the presence or absence of a particular kind of DNA, hence the organism of which it is a part. The other (not shown) is used to discover how much of a kind of DNA is present in a sample, and therefore allows estimation of microbial populations. Further back, in front of the window, is a Fischer Hamilton SafeAire Class II biological safety cabinet. When working with microbes it is well to remember that not a few are dangerous to humans, and that therefore all precautions must be taken.