Thursday, July 31, 2008

Who Makes the Most Unique DNA polymerase

Well the results from our first survey are in. I have to say, I was very surprised. When I was at a large multinational, we subscribed to various industry reports. All of them, as I recall, pointed to Invitrogen Platinum taq as being the leader in the industry when it comes to DNA polymerases...at least Hot Start. In this survey, Invitrogen scored a lowly 10% of the votes. The highest votes went to Kapa Biosystems (31% of the votes), followed by Qiagen (26% of the votes). Other votes went to Roche (15%) TaKaRa (10% tied with Invitrogen), and finally Finnzymes (5%).

So let's look at the top two:

Qiagen has a number of enzymes that have been carefully selected with optimized buffers. These include: Hot Star High Fidelity with a "special additive to the buffer", Hot Star Taq with a special blend of enzymes, Proof Start with a special buffer to prevent primer degradation, and QuantiTect SYBR Green kit which is optimized over a large linear range. When you look at all of these polymerases, they do perform very nicely as the scientists at Qiagen have spent a great deal of time optimizing the buffers. As an example, SYBR green generally inhibits PCR. Qiagen has used a careful balance with the amount of SYBR green used in its formulation to make sure the reaction efficiency is high. While this sacrifices intensity of signal, you can be assured that your reactions are indeed linear.

Kapa Biosystems takes a very different approach. Where Qiagen has focussed on the buffers, Kapa has spent its time engineered the enzyme specifically to perform better than anything else available. Their lead enzymes are Kapa2G FAST Hot Start. This enzyme can amplify at speeds up to 1 kb per second (not per minute, per second!). That means exension times of about 1-5 seconds. This, according Kapa, turns your slow cycler into a fast cycler, and save you a lot of time...and money. I can appreciate this point. Although we all say we can put the PCR reaction on, do something else for 2 hours, and then come back, the question is "why wait?" If I could get the results in 1/2 an hour or 15 minutes, I could get another run on very quickly and move my research on that much quicker....I wish that happened when I was post-doc'ing (I didn't do that much PCR when I was in grad school). We were almost scooped on a big paper. We were scooped on the follow-on study (at least part of it) and the the PCR was a time sink.

The real gems from Kapa, however, are the enzymes that handle inhibitors. Their Kapa Robust enzyme deals with a wide range of different inhibitors. It comes with two different buffers, and two sets of enhancers. A similar technology went into building their Kapa FAST SYBR kit. In comparison to Qiagen which limits the amount of SYBR, Kapa loads up on the SYBR since its enzymes are not inhibited. As a result the flouresence is through the roof, linearity is great, and combined with their FAST enzymes, it can run a slow protocol, or keep up with today's fast real-time systems to finish reactions in less than 40 minutes. The other notable enzyme is the Kapa HiFi. It claims to have the lowest error rate in the industry, runs 3 times faster than other enzymes, and handle high GC templates very well.

I look forward to hearing about how the changes in enzyme technology helps those of us at the bench. I'm sure we'll see new developments from the likes of Invitrogen to keep up. It should prove very interesting.

3 comments:

DNAcowboy said...

I'm not sure about Canada, but in Europe, Eurogentec polymerases are VERY popular.

Anonymous said...

I tried to Kapa Robust. All I can say is "Wow." Our lab had been using ABI's gold, and now we've completely switched over because of the way it handled really hard templates. I had a couple that we were working on for nearly a year. The Kapa Robust amplified it on its first try.

Anonymous said...

Yes, I was able to get the Kapa blood to work it to work on FTA genesaver cards without any rinsing. So it must be good with other inhibitors as well.

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