This entry represents the alpha-helical insertion domain of Phosphomannose isomerase type I enzymes (EC 5.3.1.8), in which the helices are packed closely, connected by short turns and loops. This domain packs closely against the catalytic domain, interrupting it [1].

1: The x-ray crystal structure of phosphomannose isomerase from Candida albicans at 1.7 angstrom resolution. Cleasby A, Wonacott A, Skarzynski T, Hubbard RE, Davies GJ, Proudfoot AE, Bernard AR, Payton MA, Wells TN; Nat Struct Biol 1996;3:470-479. PMID:8612079