Search results
Results From The WOW.Com Content Network
English: Functional proteins have four levels of structural organization: 1) Primary Structure : the linear structure of amino acids in the polypeptide chain 2) Secondary Structure : hydrogen bonds between peptide group chains in an alpha helix or beta 3) Tertiary Structure : three-dimensional structure of alpha helixes and beta helixes folded
The USDA food pyramid was created in 1992 and divided into six horizontal sections containing depictions of foods from each section's food group. It was updated in 2005 with black and white vertical wedges replacing the horizontal sections and renamed MyPyramid. MyPyramid was often displayed with the food images absent, creating a more abstract ...
Structure similarity can then be used to group proteins together into protein superfamilies. [38] If shared structure is significant but the fraction shared is small, the fragment shared may be the consequence of a more dramatic evolutionary event such as horizontal gene transfer , and joining proteins sharing these fragments into protein ...
At the top level are all alpha proteins (domains consisting of alpha helices), all beta proteins (domains consisting of beta sheets), and mixed alpha helix/beta sheet proteins. While most proteins adopt a single stable fold, a few proteins can rapidly interconvert between one or more folds. These are referred to as metamorphic proteins. [5]
Protein occurs in a wide range of food. [11] [12] On a worldwide basis, plant protein foods contribute over 60% of the per capita supply of protein. [9] In North America, animal-derived foods contribute about 70% of protein sources. [12] Insects are a source of protein in many parts of the world. [13]
The number of "common" food groups varies depending on who is defining them. Canada's Food Guide, which has been in continual publication since 1942 and is the second most requested government document after the income tax form in Canada, recognizes only four official food groups, listing the remainder of foods as "another".
A representation of the 3D structure of the protein myoglobin showing turquoise α-helices. This protein was the first to have its structure solved by X-ray crystallography. Toward the right-center among the coils, a prosthetic group called a heme group (shown in gray) with a bound oxygen molecule (red).
The CATH Protein Structure Classification database is a free, publicly available online resource that provides information on the evolutionary relationships of protein domains. It was created in the mid-1990s by Professor Christine Orengo and colleagues including Janet Thornton and David Jones , [ 2 ] and continues to be developed by the Orengo ...