Author Archives: dustinwoo

Supporting Life from Laccase to Lignin

Living in Vancouver, mosses, flowers and trees are a common sight, though the structural similarities between these seemingly different plants may come as a surprise. There are currently over 300,000 known species of plants on Earth, each with its own unique characteristics. Despite this incredible amount of diversity, one crucial component that all plants have in common is a molecule known as lignin. It is this molecule that allows a plant to grow upright with a rigid stem so that water can be transported effectively to all of its cells.

Lignin is deposited in specific ringed patterns in cell walls in a process called lignification in order to strengthen the cells. We’ve known that by having this slinky-like coiled design instead of a fixed cylindrical pattern like a drinking straw, the plant cells that deliver water are able to stretch and grow. However, the way that lignin is deposited in this pattern was not well-understood until recently; researchers at UBC have discovered that there are two key laccase enzymes, chemicals that help speed up reactions, that allow this pattern to occur.

A view of the coiled pattern of lignin in cell walls of the water-transporting plant tissues.

A view of the coiled pattern of lignin in cell walls of the water-transporting plant tissues. Each tube is one cell. Source: Leighton Dann on Flickr

In an interview with the lead researcher, Dr. Mathias Schuetz, we learned more about the importance of lignin and how his team made their discovery, as documented in the video below:

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At this point, you may be wondering exactly what the connection is between Dr. Schuetz’s research and the emerging applications, such as for the biofuel industry. With the fundamentals of lignification better understood through this research, there is high potential for improving certain industrial processes. For example, since lignin strengthens plant cell walls, it makes working with the other components of the cell wall extremely difficult, so figuring out how to remove (or even decrease) lignification without affecting other properties of plants could be extremely beneficial. As seen in the closing scene of the video, removing lignin from plants will cause them to droop. This means that accessing components like cellulose, a chain of sugars that is useful for industrial purposes, will be much easier.

Dr. Schuetz touches on details of a few implications in the following audio podcast:

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In application, decreasing the amount of lignin that goes into cell walls as much as possible without stunting the growth of the plant can provide us with raw plant material that is easier to process. Looking at the big picture, if we can substantially decrease the energy cost of processing this plant material, we can increase the yield of valuable product. This would not be possible without the fundamental understanding of how laccases are involved in lignification.

Matthew Cho, Sunny Sohn, Mikaela Stewart, Dustin Woo

Bugs in the News

We are all familiar with the fact that our bodies do not belong to us alone. We provide homes for up to 1000 bacterial species that live in our skin, our saliva, and our intestines, just to mention a few of several locations. It shouldn’t be a surprise that there is also a wide variety of multicellular microorganisms such as yeasts and mites taking refuge within us, but how many of them are we aware of? Are there more species than we realize that are living right under our noses?


Cross section view of hair follicle and sebaceous (oil) gland where face mites prefer to live. Source: Wikipedia – Sebaceous gland

It turns out that biologist Megan Thoemmes and her research team has recently found that face mites are indeed present under each and every adult nose, a recent CBC news article confidently – but questionably – reports. The two species found on human faces, Demodex brevis and Demodex folliculorum, are less than half a millimeter long, semitransparent, and either live within human pores or on hair follicles. The article reports that these creatures were found in all 253 tested adults of Thoemmes’s study, and so it is (rather pretentiously) suggested that the mites are universally existent on adult humans over age eighteen.

But isn’t the reporter jumping to conclusions?

Upon reading the original research paper, the answer is immediately clear. In actuality, there were 253 skin-scraping samples gathered, but only from nineteen participants, in contrast to the reported 253 adult participants. Extrapolating from 253 localized adults to the entire adult human population would be a hasty overgeneralization, let alone drawing conclusions from the actual sample size of nineteen. Moreover, an aspect that was completely disregarded in the article was that the participants sampled were chosen for their high apparent levels of skin-oil production, so perhaps the high frequency of face mites may not apply to everyone.


Scanning Electron Microscope image of the underside of a face mite. Source: Wikimedia Commons – Category: Demodex

In an effort to draw interest to the news article (based on the interview available in the voice clip below), the reporter used conclusive language throughout to heavily imply that all adults are hosts to face mites. By selectively filtering out some information and accompanying inferences with subtle uncertainty, along with the misreport of sample size, the article appears to be believably conclusive when in reality it is distorted and misleading, even if unintentionally so.

An example like this serves as a much needed wake-up call. Whether you’re a scientist or simply someone desiring to gain some insight into recent scientific developments and discoveries, it is absolutely essential that nothing is accepted without question. It is easy to draw conclusions from headlines as they are presented, but if proper discretion is not taken, you may be misled more than you are informed. As for whether or not we all have mites on our faces, only time and careful research will tell.

An audio clip of the interview with Megan Thoemmes is available below. Notice that a hasty generalization is made right at the start within the first minute of the track:

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Dustin Woo