Previous reports showed the PM-IRRAS spectra for urease
confined in Langmuir films of other lipids [17]. For dimyristoylphosphatidic
acid (DMPA) monolayers, the amide II bands are
reported as centered at 1527 cm−1, and the amide I bands are centered
at 1628 and 1652 cm−1. Consequently, it is probable that the
different environment provided by EPS-DODAB monolayers causes
changes in the secondary structure of the enzyme.