A late goal from Emre ended Birmingham's dogged resistance to earn Newcastle a third successive Premiership win.
The Turkish midfielder's 20-yard shot wrong-footed keeper Maik Taylor as the Blues sank to a fifth successive league defeat to remain in trouble.
Birmingham had resisted stubbornly and came closest to breaking the deadlock when Jiri Jarosik's shot struck a post.
Emre's first-half free-kick provided Taylor with a rare test.
Birmingham adopted a cautious approach with Emile Heskey ploughing a lone furrow up front and midfielders Jarosik, Stan Lazaridis and Jermaine Pennant encouraged to get forward.
The Blues certainly swamped and stifled Newcastle in midfield in the early stages and sheer weight of numbers stopped the likes of Emre and Nolberto Solano having any influence on matters.
Newcastle's first threat came from an 18th minute set-piece when Emre whipped in a free-kick and Blues keeper Taylor did well to palm the ball away after seeing it late through a ruck of players.
Laziridis spat out a tooth following a clash of heads with Titus Bramble and the Australian's afternoon took another downturn when referee Mike Dean booked him for diving after Scott Parker appeared to clip him in the penalty area.
Newcastle also had a penalty appeal waved away when referee Dean ruled the ball had struck Matthew Upson's arm.
Birmingham were dogged in their resistance and Izzet epitomised their effort when he bravely threw himself in front of Charles N'Zogbia to block his shot.
Emile Heskey and Titus Bramble go head to head
Solano curled a free-kick into the side-netting while at the other end Jarosik volleyed wide from 10 yards from Upson's knock-down.
Jarosik came within a whisker of ending Birmingham's 375-minute goal drought with an impudent effort from fully 45 yards which hit Shay Given's left-hand post and then Upson headed inches wide from a free-kick.
Birmingham continued to frustrate Newcastle who did not help their own cause by wasting a series of free-kicks in dangerous areas with some woeful deliveries.
The visitors looked to have claimed a priceless point when Emre broke their hearts.
Nobody appeared keen to take responsilibity as Newcastle elaborately passed the ball around the box but eventually Shola Ameobi laid it into the path of Emre whose powerful shot wrong-footed keeper Taylor.
Newcastle boss Graeme Souness
"It wasn't a good game of football and you've seen two Newcastles in the space of seven days.
"At West Brom we were attractive but today it was about scrapping with a team who are fighting for their lives.
"It was a scrappy affair but we've got the points. We've all been involved in games like that and we will be involved in games like that again.
Birmingham boss Steve Bruce:
"The goal was very disappointing. At first I thought Emre's shot was deflected but it didn't take a deflection.
"It was in the middle of the goal and Maik should have done better with it. It was a mistake and he knows that.
"We have to keep believing and I thought we deserved more than we got."
Newcastle: Given, Ramage, Taylor, Bramble, Babayaro, Solano (Clark 82), Parker, Emre, N'Zogbia (Ameobi 57), Shearer, Owen.
Subs Not Used: Elliott, Harper, Faye.
Booked: Taylor, Shearer, Emre.
Goals: Emre 78.
Birmingham: Maik Taylor, Cunningham, Martin Taylor, Upson, Clapham, Pennant, Izzet (Forssell 86), Kilkenny, Lazaridis (Pandiani 86), Jarosik, Heskey.
Subs Not Used: Vaesen, Tebily, Painter.
Booked: Lazaridis, Izzet.
Referee: M Dean (Cheshire).