Visiting the original PCR
August 20, 2024
Originally from 2014
A trip to the USA last year (JM: 2013!) was a a chance to mix business with pleasure. Usually these are two separate entities but one that combined both occurred on a trip to the Smithsonian Institute (American History Museum) in Washington. While Belinda headed off to see the First Ladies’ dresses, I was lucky enough to head behind the scenes to a particular storeroom in the Smithsonian. This in itself is not particularly exciting since the Smithsonian only has a fraction of its items on display at any one time so must have more storerooms than display rooms!
But I was going to see Mr Cycle.
As a background, the early days of PCR involved water baths, a stopwatch. . . and a lot of boredom. Manually transferring reactions from 95°C to 30°C and adding the heat-labile Klenow at each cycle was tedious (and expensive! 2U of Klenow per cycle – per reaction – quickly adds up). And so thoughts turned to automation. Cetus engineers modified a pipetting station they had built (Pro-pette): using hoses to cycle water to heat and cool a tube block and holding another block (holding the tubes of Klenow) at 4°C.
And in a small storeroom, out of its usual cupboard, there it was:
Not only did the storeroom contain Mr Cycle . . .but also ‘Son-of-son-of-Cycle’. No, it’s not known where ‘Son-of-Cycle’ is and as it turns out, SOSOC is believed to be about thermalcycler #5 or so. Now in the era of Taq polymerase, it was the first Peltier instrument:
Many thanks to the biotechnology curator assistant Mallory – for not only kindly taking time to show me the PCR instruments and other interesting items but for also kindly taking a few photographs. Yes of course I wasn’t going miss the chance for a photo with a chunk of steel, some blocks and black hoses – photo now heading my LinkedIn profile. Oh, and Twitter profile as well
After talking about qPCR with Mallory and the original equipment for that, I made contact with someone else in the USA: someone else who used to work at Cetus and upon sending him the photo, he responded ‘that was my first job at Cetus, learning to program ‘Mr Cycle’. (JM: the subject of that post can be found here)
