OSU Microbiology

Well Known Schools that teaches Microbiology

Pharmaceutical and Generic Engineering firms are searching for Microbiologist. If you are in U.S and are in need of the best school that provides the best education for those who wanted to become a Microbiologist, the top 4 includes Harvard University, Stanford, University of California—​Berkeley, and University of Wisconsin—​Madison. These top 4 Universities are considered to be the best option to provide the best possible education for you.


Methanogenesis and genetically encoded pyrrolysine in Archaea.

Joseph A Krzycki


Ph.D. 1985. University of Wisconsin-Madison.


Interest in methanogenic microbes first revolved around their economic potential and impact on human activities and the environment. A methanogen s existence depends on producing large amounts of methane, an alternative energy source; and they make methane while carrying out the final stages of the breakdown of organic material in important environments like lake sediments, cattle and sheep rumen, and sewage digesters.

But as knowledge of methanogens expanded, so have the reasons for studying them. They were the first organisms identified as members of the Archaea, a domain of life evolutionarily separate from Bacteria or Eucarya. Methanogens possess an unusual biochemistry and molecular biology, and have distinctive cofactors and enzymes to form methane. In recent years we have shown that some methanogens have even adapted their genetic code to serve the end of methanogenesis. This has led to our studies of the novel genetically encoded amino acid, pyrrolysine.

Methanogenesis from methylamines.

Our lab studies Methanosarcina spp. because this genus can convert more compounds to methane than most other methanogenic genera. We asked how such pathways evolved, and demonstrated that making methane from one set of compounds, the methylamines, required recruitment of specialized methylamine methyltransferases that methylate corrinoid cofactor (a vitamin B12 derivative) bound to a partner protein (Burke et al., 1997; Ferguson et al., 1997, 2000; but see also Tallant 2001). As we sequenced the genes encoding one of the methylamine methyltransferases, we found it contained an in-frame amber (TAG=UAG) codon (Burke et al., 1998). Amber is normally a stop codon and so we began a several-year long quest to understand the amber codon connection to methanogenesis. We found single amber codons were in all methylamine methyltransferase genes, that the amber codon remained in the mRNA made from them (Paul et al. 2000), and that UAG was translated (James et al, 2001). We then collaborated with the lab of Michael Chan, who solved the structure of a methylamine methyltransferase and further deduced the structure of the amino acid that corresponds to the UAG codon (Hao et al, 2002). This was the first glimpse of pyrrolysine.

The direct genetic encoding of pyrrolysine.

 Our subsequent studies have shown that pyrrolysine has directly entered the genetic code much like the original twenty amino acids. Pyrrolysine has its own tRNA (called tRNAPYL or tRN CUA ) that can decode UAG (Srinivasan et al., 2002). A gene called pylS follows the tRNAPYL gene in the methanogen genome. The protein made from pylS is a pyrrolysyl-tRNA synthetase. That is, this enzyme attaches chemically synthesized pyrrolysine (Hao et al. 2004) directly to tRNAPYL , a key step that allows pyrrolysine entrance to the genetic code (Blight et al., 2004). This was the first time an aminoacyl-tRNA synthetase was found for any amino acid other than the common twenty amino acids.

UAG is both stop and sense codon in Methanosarcina. 

We have found the methanogen still uses UAG as a stop codon (Longstaff, Blight et al., 2007); and a balance exists between use of UAG as a stop codon and a sense codon within Methanosarcina acetivorans. In genes that don�t normally code for a pyrrolysyl-protein, the balance is tipped in favor of UAG as a stop codon, and only a fraction of the UAG is translated as pyrrolysine. For one of the pyrrolysyl-proteins, the balance is tipped toward mostly UAG translation as pyrrolysine. A downstream enhancer sequence (called PYLIS) is important in this process. In the absence of PYLIS, pyrrolysine insertion into protein is much less efficient. This is important for methanogen survival, as high amounts of methyltransferase are made, and methanogens gain little energy from making methane from methylamines.

 Biosynthesis of pyrrolysine.

 Nearby the pyrrolysyl-tRNA synthetase and tRNAPYL genes are three more pyl genes, pylB, pylC,and pylD. The enzymes from these genes are responsible for making pyrrolysine from common cellular metabolites (Longstaff et al., 2007). This is distinct from the ligation of the amino acid to tRNAPYL . The pathway is yet unknown, but several are possible (Krzycki, 2004; Longstaff et al. 2007) and we are now investigating the activities of the individual enzymes.

The genetic encoding and biosynthesis of pyrrolysine can be transmitted to other organisms.

 We have shown that the transfer of the pyl genes to a na .ve bacterium imparts the ability to make pyrrolysine and to translate UAG codons as pyrrolysine (Longstaff, et al. PNAS 2007, but see also Blight et al., 2004). In other words, the genetic encoding of pyrrolysine can be transmitted from organism to organism with only five genes. This has led us to propose that genetically encoded pyrrolysine could be spread from microbe to microbe in the environment. Such a genetic code expansion may have already happened in nature as illustrated by a gram positive Bacteria called Desulfitobacterium hafniense, which possesses all five of the pyl genes much like would be found in the methanogen (Srinivasan et al., 2002).

Function of pyrrolysine in methanogenesis.

Why was pyrrolysine recruited to the genetic code of methanogens? To answer this question we deleted the tRNAPYL gene and found the only detectable defect in the mutant was an inability to make methane from methylamines (Mahapatra et al, 2006). We have further found methylamine methyltransferases lacking pyrrolysine are not functional, and are investigating the underlying enzymology. This has brought our studies back to our original question of how Methanosarcina spp. evolved the ability to make methane from methylamines. Our earlier studies showed the evolution of methanogenesis from methylamines required the ability to make methylamine methyltransferases, our latest studies showed that the ability to make those methyltransferases quite literally meant they had to remodel their genetic code to include a novel amino acid.


DJI Phantom 3 vs Yuneec Typhoon 4k Drone Comparison

Its a fact that majority of drone enthusiasts out there recognize what Phantom family of drones do. Now, when you mention a brand like Yuneec, people begin drawing blanks in their head since the brand is not as popular.

Well, if youre looking for a direct comparison between DJI Phantom 3 vs Yuneec Typhoon 4k Drone, you might be in for a surprise as you continue reading this piece of information.

First, we can say that the Yuneec brand has drones that offer enormous value for their worth and the amount of money youre paying. The same can be said about the top turntables out there. In fact, some users even argue that Yuneec brand manufacturers drones that are as good as their Phantom counterparts.

No doubt, the Yuneec range of drones for sale are fast becoming popular in the quadracopter category of drones. In fact, the Yuneec Typhoon 4k Drone can now be compared directly to the DJI Phantom in both specs, capabilities and price.

The price of both drones

Its worth taking note that both drones command almost the same price tag. The Typhoon 4k sells at a price that is relatively higher than that of its DJI Phantom counterpart. The retail price for both drones is $1,299 and $1,259 respectively. In addition to his, both drones are very similar in design as well as video capturing capabilities (HD 1080p video quality).

DJI Phantom 3 vs Yuneec Typhoon 4k Drone Comparison

The features

If youre a starter, both drones will serve you well because they are ready to fly out of the box. Once you charge the battery, both drones will be ready to hit the skies. This way, you can capture some truly amazing UHD video footage coupled with high-megapixel images of the landscape youre pointing the drone towards.

Another factor worth noting is that both drones tend to be very user-friendly. Ease of control means a beginner will have very little to no problem when it comes to flying their new acquisition.

Also, the hand-held controller has a feature that works with the transmitter signal to relay real-time live DH feed of the videos and photos being shot. This feature is known as first person viewing (FPV).

Nevertheless, in as much as the mentioned features are available in other standard drones, the fact remains that these features have been incorporated into both drones in a way that they present less problems and more user-friendliness to newbie users.

However, there are still some significant differences between the Yuneec and Phantom. Most of these differences work towards favoring the Yuneec Typhoon 4k.

The slight differences

The Yuneec Typhoon has a carry case and a pair of batteries instead of one. However, if we talk of the Phantom, we realize that users have to purchase a carry case separately, plus theres only one battery to go with the purchase, not two.

Whats more, the Phantoms controller doesnt have a touchscreen either. So you have to pair it with your smartphone to be able to view what the camera is seeing in the air. In this case, you will have to download the Phantom app.

On the other hand, the Yuneec Typhoon Q500 4k has a touchscreen on its controller, and this kind of display can be used to control all elements related to the drone and video settings.

The Yuneec Typhoon included a feature called Steady-grip. The Steady-grip feature is a hand-held mount of the 4K camera. This can also be detached from the unit so it can be used on other ground-based 4K video tasks.


In general, the DJI Phantom 3 is the most popular of the two drones for sale. It offers a lot of value indeed. However, it seems that the DJI Phantom 3 still lags behind in other prominent features, and thats the reason why the Yuneec Typhoon is fast gaining ground.

Well Known Schools that teaches Microbiology

Pharmaceutical and Generic Engineering firms are searching for Microbiologist. If you are in U.S and are in need of the best school that provides the best education for those who wanted to become a Microbiologist, the top 4 includes Harvard University, Stanford, University of California—​Berkeley, and University of Wisconsin—​Madison. These top 4 Universities are considered to be the best option to provide the best possible education for you.

The Difference Between Cell Biology and Microbiology

Cell Biology and Microbiology are almost simultaneous with each other every time we hear of these two disciplines. Somehow, there is a difference between the two as Cell Biology deals with the Cells in the human body, animals, plants and other living organisms while the Microbiology are for those that deals with microorganisms such as viruses and bacteria.

What is Microbiology

Microbiology relates to the science or study or bacteria, viruses, fungus and other small bits or organisms that are found in every life forms.Most of these microorganism cannot be seen by the naked eye and would need a special apparatus to be identified