Ammonia lyase belongs to the family of enzymes that catalyzes the deamination of amino acids. Depending on the relative activity towards the substrates, L-tryptophan ammonia lyase converts L-tryptophan to indole 3-acrylic acid and ammonia. Here, we isolated, purified, and characterized an L-tryptophan ammonia lyase from phototrophic purple non-sulfur bacterium Rubrivivax benzoatilyticus JA2. The isolated L-tryptophan ammonia lyase found to catalyze the reaction of L-tryptophan to produce indole 3-acrylic acid and NH3. The enzyme is a heterotetramer and has the highest affinity to L-tryptophan. The optimum pH and temperature for the enzymatic action were 7.5 and 35°C, respectively and the Km and Vmax were 40.4 ± 23.1 nM and 0.964±0.2046 s(-1), respectively. These results suggest that the isolated enzyme is highly bioactive and could be a new class. Further molecular analyses are required to confirm the novelty of the enzyme.