Described herein are oligosaccharyl transferases for use in N-glycosylating proteins of interest in vitro and in host cells. Methods for using such oligosaccharyl transferases, nucleic acids encoding such oligosaccharyl transferases, and host cells comprising such oligosaccharyl transferases are also provided herein. Glycoconjugates generated by using such oligosaccharyl transferases are also provided herein.