The Turkish elections and the Turkish Stream pipeline
Regardless of Turkish elections results, energy minister Taner Yıldız was going to be leaving his post anyway, because of the term limits on AK Party members that its de facto (because in Turkey the president should in principle be above party politics) leader Recep Tayyip Erdoğan introduced into the party structure. The purpose was to have perpetually new parliamentarians (permitted to run only twice for reelection), who would therefore be more beholden to Erdoğan than if they could have institutionalized their place in parliament. But now the whole question of who will constitute the government is up in the air.
There is even a never-used provision of the Turkish Constitution that permits the President to refuse to approve a minority coalition government, which may be well in the cards since the MHP and HDP are unlikely to be able to serve in the same cabinet. Things are still very fluid, but most likely is HDP remaining outside government and supporting a CHP-MHP coalition, much as the Italian communists did in the 1970s under the compromesso storico.
Whether there is a coalition government or not (and one supposes now that there must be), and Erdoğan would decline to support a minority coalition or not (unpredictable as ever), the allocation of ministerial portfolios and the attribution of negotiating authority with Russia over Turkish Stream, which still does not have a bilateral contract for construction (since environmental permits on the Turkish side are still lacking), not to mention for sale and purchase of the gas, will be in limbo for some time to come. This will not prevent the Russian side from continuing to lay pipeline on the Black Sea bed in the Russian sector, which work has already begun, but it will not at all help to guarantee that Turkey will buy any gas in the end.