Proteins are subatomic biomolecules. They're produced by cells, so it's logical to assume that they are much tinier than cells, and of course, much tinier than the organelles that produce them. In a remarkable achievement, scientists have now obtained the first-ever photographs of single proteins. Using a "holography electron microscope," researchers tested on a range of protein samples, all just a few nanometers in size. Hemoglobin, the protein that transports oxygen in red blood cells, and cytochrome c, the protein that transfers electrons within the body, were just two examples.

Source: arXiv ...

Researchers have uncovered the mechanism that allows spiders to build such strong webs. According to the study, both ends of the spider's silk grand have different pH levels, which helps these proteins become a solid fibre that can be spun into a solid web. The researchers also found that the pH level has different effects on the stability of the two regions at each end of the spidroin proteins.

“While one of the ends tended to pair up with other molecules at the beginning of the duct (N-terminal) and became increasingly stable as the acidity increased along the duct, the other end (C-terminal) destabilised as the acidity increased, and gradually unfolded until it formed the structure characteristic of silk at the acidic pH of 5.5”, ex ...

Titin is the largest known naturally occurring protein and is composed of 34,350 amino acids. It is also known as connectin and is abundant in striated muscle. Though it is 189,819 letters long, its status as the longest word in the English language is debatable, given that it is a technical word not found in the dictionary. ...