We are looking into this as well. We think our branch may have spelled it Petri before coming to the states:

Phillip and Elizabeth (Gentes) Petre. Sons Christian b. 1851 and Phillip come to America in 1873 on the ship Donau. Christian settles in Cullman, AL by 1880 where he is already widowed with three kids. Settles in Buffalo, NY. He is remarried and has several more children before moving to NYC around 1900. Lives in Queens and Brooklyn over the span before he dies in 1924.