The Ottoman Empire in WWI had managed to join the Central Power and had hence formed the Triple Alliance. This was sealed off with the signing of the Turco German Alliance which took place in August of 1914. Hence with the bombing of the Russian Black Sea ports, Turkey had finally, formally entered into the World War I. Seeing this Triple Entente or which is called the Allied Powers had announced war on the Empire on the 4th of November the same year. #
There were two major factors which helped in the involvement of this Empire to the side of the Central Powers. The first was the part about the German pressure and the second was the opportunistic motives of the Turkish Prime Minister of war who was Enver Pasha at that time. There were other motives for the Ottoman Empire in WWI on the side of the Central Powers. This was the friction which was present between Turkey and the Tripe Entente.
Germany had a clear aim; it wanted to prevent Turkey from joining the opposition army. The military mission of Germany in 1913 the one which was to Turkey had led to a secret treaty which was signed in August 1914. The Allies on the other hand had interest which were strategic in nature which involved the Turkish Straits but then they couldn't provide a defence of Turkey which was from Germany.
According to Enver Pasha the Ottoman Empire in WWI was simply like a little pawn in a game played by Germany where Germany wasn't really a strong competitor. Pasha defended his decision to ally with Germany citing that Germany was strong and had made many conquests in the beginning. He also said that it would help in saving the Ottoman Empire from disintegration.
The alliance with the Central Power had appealed more to the Ottoman Empire in WWI for different other reasons. The first was that Turkey had clashed along with the Allies because of the harbouring of the German warships. The second was because of Russia's interest in the Turkish Straits. In 1912 the Balkan wars had shaken Russia into thinking that they would lose any control over the territory they could get. But in 1913, Russia had threatened the Empire saying that if the German troops weren't removed then they would occupy the territory under the Ottoman Empire.