Former France playmaker Micoud played for both clubs, and according to Obraniak he had no hesitation in recommending Bremen and the German league.
"Johan is an icon in Bremen. He is an important contact for me and advised me to make a switch to Werder," Obraniak said on Bremen's website.
"We know each other well, we both live in Bordeaux. He said that my style of play would fit in superbly in the Bundesliga.
"We spoke about life in Bremen too. He only said positive things about the people, the city and the club."
Bremen announced Obraniak, a full Poland international, has signed a two-and-a-half-year contract.
He spent two years at Bordeaux, joining from Lille in January 2012 and scoring 16 goals in 91 appearances, playing in the side that beat Evian in last season's Coupe de France final.