With regard to the Biological Nitrogen Fixation by Rhizobium in association with soyabean, which one of the following statement/statements does not hold true?
1. Nitrogenase may require oxygen for its functioning .
2. Nitrogenase is MO-Fe protein.
3. Leg-hemoglobin is a pink coloured pigment.
4. Nitrogenase helps to convert ${\mathrm{N}}_2$ gas into two molecules of ammonia. 

Identify a free living anaerobic nitrogen fixing microbe:

Name the amino acid from which 17 other amino acids are formed by transamination in plants?