Seafood is an excellent source of protein because it's usually low in fat. Some proteins have lower quality as they may be missing or have lower amounts of a specific amino acid. Most individuals need 5 to 7 ounces of protein every day. Protein content: 21% of calories. Every cell in your body contains protein, so meeting your protein requirement is … Integral proteins may have their own transmembrane domain or may be linked with some special type of … For example, legumes are lower in methionine and grains are lower in lysine. This is not usually a problem as we eat more protein then we need in a day.” Are there different types of protein that help for athletic performance? Protein can be found in animal sources like meat and dairy products, or plant sources like beans, nuts and seeds. Proteins are composed of chains of amino acids. They are held inside the membrane by hydrophobic interaction. Proteins that are embedded deeply in the plasma membrane are integral proteins. One cup of whole milk contains 8 grams of protein and 149 calories ( 10 ). A typical protein is about 400 amino acids long. Seafood. Integral Proteins. One cup of soy milk contains 6.3 grams of protein and 105 calories ( 11 ). One ounce of protein can be obtained through 1 ounce of meat, poultry or seafood. According to the USDA, 10 to 35 percent of your calorie intake should come from protein. Classifications may be based on protein structure as in the CATH database and the Structural Classification of Proteins database (SCOP). Protein Equivalents. List of proteins contains large amounts of information concerning genes and proteins.Gene and genome sequencing projects have led to the creation of many gene databases and attempts to organize all of the available information. If you don’t eat animal products, it’s important to eat many different types of plant proteins to get enough essential amino acids. Collagen (/ ˈ k ɒ l ə dʒ ɪ n /) is the main structural protein in the extracellular matrix found in the body's various connective tissues.As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole-body protein content. 5 Roles of Protein.