5 ms·
The headline is potentially confusing, it doesn't mean that this is the first time individual atoms were measured, but the first time this particular method has
by fabian2k 6y ago
The headline is potentially confusing, it doesn't mean that this is the first time individual atoms were measured, but the first time this particular method has been pushed to such a high resolution that individual atoms could be distinguished.
Cryo EM is a very hot method right now to determine the three-dimensional structure of large molecules like e.g. proteins or protein complexes. Something like 10-15 years ago the best you could get was maybe 1.5 - 2 nm (these are rough numbers from memory), the results described in the article are 0.17 nm.
- jjoonathan 6y agoFurther, atomic resolution is routine in electron microscopy, it's specifically Cryo EM (a sub-technique aimed at imaging proteins, which are extremely fragile compared to, say, chunks of metal or computer chips) where the advance has happened. This is phenomenal! The title still feels a bit sensationalized, but don't they all?
- m4rtink 6y agoCryo EM is really cool (not just in temperature! ;-) ) technology! :) Recently I had a chance to go on a tour in the two-part CEITEC research center in Brno, a city with long history of electron microscopy manufacturing and research. One part of the CEITEC research center does "dry" tech - chemistry, robotics, motor and machine control and chips. Of course, they have quite a lot of cutting edge electron microscopes to image various nano structures. All looking super high tech as you watch their shiny metal over the clean room window. All the machines stand on concrete slabs embedded into the hill below the building to avoid vibrations and have ultra high vacuum inside. The other part of CEITEC does "wet" research - proteins, cells, bacteria, microorganisms. Of course also they have cutting edge, cry electron microscopes. These looked quite different to the other ones - it was a huge black cube, reaching almost the high ceiling of the room. You could not see all the glistening internal components like in the previous case. In this case they even let us to the room itself - apparently given all the volatiles in the samples, the cleanliness requirements in the room containing the machine are not as strict & it likely (my guess) needs to keep quite a bit part of the machine at very low temperatures, explaining all the covers. IIRC the software controlling the camera runs on Linux & engineers from Brno working for one of the big EM manufacturers were involved in building this enormous cryo EM machine, which was a pretty nice touch. :)
- natechols 6y agoWhen I started grad school in 2003 there were a handful of structures approaching 0.4 nm, which is the point where you might be able to build most of the sequence into the map de novo. But those were exceptional cases.
- dekhn 6y agomy favorite report from grad school was the paper that had to be retracted because they "built the sequence into the map backwards" (IE, the N and C termini were switched).
- natechols 6y agoWas that the Great Pentaretraction or something else? My favorite is still the Krishna Murthy structures that turned out to be completely made up.
- ryanmt 6y agoWhen I was doing this in grad school in 2009, we were pulling down to 10 angstroms in our best 3d reconstructions, sampling something around 30k virus particles (which I and some undergrads got to pick from the chromatographs).
- dang 6y agoTitle changed now (see https://news.ycombinator.com/item?id=23423910 https://news.ycombinator.com/item?id=23423910).
- deleted 6y ago[deleted]