Thank you for taking the time to produce these podcasts free of charge. I hope this style of science podcasting continues to inspire other scientists into creating similar podcasts.
On TWiM #17, you discussed the discovery that mealybugs have symbionts within symbionts, which you guys related to the mitochondria. Until this year, I was consistently taught that mitochondria are individual sausage-shaped organelles. Due to their size, shape, and molecular data, they appeared to be a bacterium that was phagocytized. However, I have now come to learn that mitochondria are truly a reticulum similar to the endoplasmic reticulum. Interestingly, this information was known as early as 1980 when Ezzatollah Keyhani (from Tehran, Iran) published a paper (Observations on the mitochondrial reticulum in the yeast Candida utilis as revealed by freeze-fracture electron microscopy, Journal of Cell Science, 46, 289-297) describing it as a branched reticulum. The shape commonly used in textbooks is really just cross sections through the reticulum.
My question is: how did these phagocytized bacteria acquire the reticulum? Were these started as pili that have since evolved into a reticulum? In addition, why do textbook authors still present the sausage-shaped mitochondria in textbook diagrams as opposed to the reticulum? Why has not there been a greater push in academia to present the mitochondria as a reticulum?
This whole idea made complete sense when I viewed the mitochondria as small sausage shaped alpha proteobacteria. I performed a quick literature search but was not able to find any literature examining this question.
Thank you and keep up the excellent work,
1st year PhD student
I absolutely love listening to you guys. I have learned so many things from listening to TWiV, I am sure I will have be a step ahead when I take my advanced biology classes. One question though, Once a certain strain of bacteria becomes resistant to antibiotics, how much do these antibiotics need to be modified to combat an illness caused by this bacteria that has grown resistant? I have done research on this question, but so far I have not found an answer. I hope you guys can help me out with informing me about this process.
Thanks in advance,
the other day I was in a discussion about what can get cancer, something that ultimately boiled down to what cancer really is. Our reasoning went along the lines of establishing that there are organisms containing any number of cells, ranging from one and up. If I remember correctly, C. Elegans has 957 cells. Presumably there is some organism with 956, 955 and so on.
It seems it doesn't make any sense to talk about a one celled organism developing cancer - though I am interested to have that confirmed! The nematode just mentioned has cell specialization, so it could presumably develop some form of cancer. What is the lower limit of cells an organism must have to succumb to the decease or should the question really be posed in a completely different way?
Also, some organisms of very few cells occasionally gang up and form a super-organism. This includes some slime moulds and the pre-larvae state of jelly fish. Can such "temporary" organisms develop cancer?
The question is grander than just parasites, and I have a feeling that viruses, living or not, have no propensity to develop cancer. Hence my addressing the question to TWIM.
While I have your attention, allow me to once again thank you and everyone in each of the podcast teams for your effort in sharing your knowledge and doing it in such an enjoyable tone and fashion.
All the best,
Stan Maloy writes:
I was visiting the University of New Mexico last week and ran into a scientist who said that he LOVES TWIM. His only complaint was that he commutes a long distance on his bike and sometimes gets so caught up in the discussion that he has nearly avoided an accident. Not faint praise from a scientist who is known for being extremely critical.