Glutamine and glutamate are two important amino acids present in living organisms.  There are several differences between the two: 

Glutamine: 

• Is a conditionally essential amino acid – the demand increases with elevated levels of stress or in case of diseases 
• Is used in the biosynthesis of proteins
• Does not have a charge
• Functions – maintains ionic balance inside the kidney, is an energy source and acts as carbon and nitrogen donor for various biochemical processes. 

Glutamate: 

• Is a non-essential amino acid synthesized by alpha ketoglutaric acid
•  Is the most abundant neurotransmitter in the brain
• Is vital to brain health, specifically learning, memory, and synaptic maintenance 
• Has a negative charge 
• Functions – plays an integral role in normal braining functioning and the formation of cytoskeleton and acts an vital metabolic intermediate that builds proteins