Self Assembly

"Amino acids that prefer to be next to one another, like a group of greasy ones, might associate to form one domain; amino acids with negative charges might line up next to amino acids with positive charges to form a second domain; a bulky amino acid might cause a protuberant domain to stick out farther. This all happens spontaneously -- the process is called self-assembly -- and the result is a protein with a distinctive overall shape and size that displays a collection of very specific domains."