How to choose the right programming language or framework to build micro services

Currently I'm trying to develop the first micro service for a very busy website we are operating, its platform is composed from many layers :

• Nginx as the main LB
• a Transaction server programmed with C, communicating with the Database
• PHP server, hosting few modules coded using PHP
• Mod_templates, custom coded templating engine with C communicating with the Trans server to get data and serve HTML DOM
• Redis servers to store and manage current users sessions
• Search engines custom coded with C to fully index some tables
• Custom Apache server with tweaked mod_sec and mod_templates

The website currently receives 300,000+ visits daily, and our vision is to move to micro services, so we can easily move the new platform to Amazon and work on auto scaling part.

The challenge here is how can we know the right programming language to choose for every micro service, and is there any known frameworks with small-footprints to build a micro service with ?

Actually I'm benchmarking Perl, RoR, Django, and NodeJS. What is the language with less dependencies or let's say the smooth one.

Should we respect some patterns like MVC so we can build an easily maintained micro service or keep things very simple and plain ?