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. ...

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 ...

Some organisms, such as the castor bean plant (Ricinus communis), produce substances that inhibit the synthesis of proteins (called translation) within a cell. (The plant, which is native to Africa, is not related to the species of bean plants with which you are likely more familiar.) A protein called ricin, produced within the castor seeds is an extremely potent inhibitor of protein synthesis. In fact, it is one of the strongest natural toxins produced. A single chewed seed can kill child! If the ricin were purified, it would take an amount equivalent to only a few grains of salt to kill an adult. Ricin kills cells by enzymatically cleaving covalent bonds within the large and small ribosomal subunits, rendering the protein-building factori ...

As soon as we're born, we're destined to age. Some of us age gracefully - we enjoy years of youthfulness - while others experience hair loss, wrinkles, and greying earlier than expected.

Found in the core of each hair, a pigment known as melanin gives rise to a person's hair color. This universal pigment is also found in our skin and eyes, giving use our unique physical traits. Dark and light versions of melanin - eumelanin and phaeomelanin, respectively - combine in various combinations to create all natural hair colors.

Melanin itself is the product of a specialized cell, the melanocyte, which is found in each hair follicle, from which the hair grows. As hair grows, the melanocyte injects melanin into the hair cells, which contain the s ...