He has moved from Hull City to MLS outfit Atlanta United for an undisclosed fee believed to be about £1.5 million.
Alzate became a regular for the Tigers in the second half of last season but has now departed Humberside.
The Colombia international was seen as the face of a bright new start under Graham Potter five years ago.
Initially used as a wing-back, he emerged in the first team with Aaron Connolly, who is now at Alzate's first club Leyton Orient.
Alzate went on to play for Standard Liege on loan for two seasons and left the Seagulls last summer.
Read more...
He has signed a contract until 2020 with Atlanta, who are 13th in the 15-team Eastern Conference and have lost their first two games in the Leagues Cup.
They are coached by former Celtic boss Ronny Deila.
Alzate made his international breakthrough when he was playing for Potter’s Albion side and earned the last of his seven caps for Colombia in 2022.