Muthusamy Palaniswamy

Microbes make a remarkable contribution to the health and well-being of living beings all over the world. Interestingly, pterin deaminase is an amidohydrolase enzyme that exhibits antitumor, anticancer activities and antioxidant properties. With the existing evidence of the presence of pterin deaminase from microbial sources, an attempt was made to reveal the existence of this enzyme in the unexplored bacterium Agrobacterium tumefaciens LBA4404. After, the cells were harvested and characterized as intracellular enzymes and then partially purified through acetone precipitation. Subsequently, further purification step was carried out with an ion-exchange chromatogram (HiTrap Q FF) using the Fast-Protein Liquid Chromatography technique (FPLC). Henceforward, the approximate molecular weight of the purified pterin deaminase was determined through SDS-PAGE. Furthermore, the purified protein was identified accurately by MALDI-TOF, and the sequence was explored through a Mascot search engine. Additionally, the three-dimensional structure was predicted and then validated, as well as ligand-binding sites, and the stability of this enzyme was confirmed for the first time. Thus, the present study revealed the selected parameters showing a considerable impact on the identification and purification of pterin deaminase from A. tumefaciens LBA4404 for the first time. The enzyme specificity makes it a favorable choice as a potent anticancer agent.

Violacein was isolated from Chromobacterium vaccinii CV5, a Gram negative bacterium collected from the Well water near a paddy field- Nedumangadu, Kerala, India. In the current antioxidant study, the activities of violacein were analyzed by different scavenging assay. In vitro antioxidant activity of violacein pigment was studied with the antioxidant, hydrogen peroxide DPPH, nitric oxide, hydroxyl and superoxide. The results suggest that the violacein possess potent activity of antioxidant against DPPH, superoxide, nitricoxide, hydrogen peroxide and hydroxyl with IC50 values of 297.88 µg/mL, 312.89 µg/mL, 410.17 µg/mL, 296.74 µg/mL and 292.74 µg/mL respectively. The activity was comparable with the standard L-ascorbic acid. Natural compounds are very much used for the treatment of chronic diseases because of their effectiveness and have less harmful as compared to synthetic and artificial drugs. The present study’s shows the ability of the pigments as a source of natural antioxidants which has various applications in pharmaceutical industries.

Pterin deaminase is an amidohydrolase enzyme which hydrolyses pteridines to produce lumazine derivatives and ammonia. Even though the enzyme was shown as early as 1959 for its anticancer efficacy there was a long gap in the communique after that which was in 2013. In our study we have chosen Mucor indicus MTCC 3513 which was a promising strain for production of different industrial products.The pterin deaminase enzyme was harvested and extracellular from M. indicus. The extracellular sample was partially purified by using ethanol precipitation and ion exchange column (Hi-Trap QFF) in Fast Protein Liquid Chromatography. The molecular weight of the purified pterin deaminase enzyme was apparently determined by SDS-PAGE. The purified enzyme was further biochemically characterized. Molecular docking studies with the predicted sequence showed higher binding affinity towards folic acid interaction. The structure of this protein may open the windows for new drug targets for cancer therapy.

Alkaline proteases have high commercial value and find multiple applications in various industrial sectors. The present study intended to isolate a suitable bacterium for alkaline protease production. Protease producing bacteria were isolated from organic waste containing soil, screened for protease production on skim milk agar plates and confirmed the protease production through protease assay. The bacterial isolate showing highest alkaline protease production was selected and identified by microscopic, macroscopic, biochemical and 16 S RNA phylogenetic analyses as Bacillus cereus FT 1. Maximum enzyme production by the isolate was obtained at 35°C; pH, 9.5; 2% lactose as a carbon source and 3.5% casein as a nitrogen source after 48 h of incubation. Among the various surfactants tested, tween 20, tween 80 and poly ethylene glycol were found to be increasing the protease production by the isolate. Mn2+, among the metal ions tested tremendously increased the protease production. The best organic solvent for protease production was found to be petrol. With all the optimised cultural conditions, maximum enzyme activity was found to be 187 U/mL and the enzyme was a promising one for detergent industry as an additive enzyme.

Microbes being the initial form of life and ubiquitous in occurrence, they adapt to the environment quickly. The microbial metabolism undergoes alteration to ensure conducive environment either by degrading the toxic substances or producing toxins to protect themselves. The presence of cyanide waste triggers the cyanide degrading enzymes in the microbes which facilitate the microbes to utilize the cyanide for its growth. To enable the degradation of cyanide, the microbes also produce the necessary cofactors and enhancers catalyzing the degradation pathways. Pterin, a cofactor of the enzyme cyanide monooxygenase catalyzing the oxidation of cyanide, is considered to be a potentially bioactive compound. Besides that, the pterins also act as cofactor for the enzymes involved in neurotransmitter metabolism. The therapeutic values of pterin as neuromodulating agent validate the necessity to pursue the commercial production of pterin. Even though chemical synthesis is possible, the non-toxic methods of pterin production need to be given greater attention in future.

As early as 1974, reports have confirmed the anticancer activity of pterin deaminase isolated from fungi. The enzyme has also been reported in bacteria, fungi and slime mold genera, but the enzyme characterization was effetely done. The present study attempted to purify and characterize pterin deaminase enzyme from Saccharomyces cerevisiae NCIM 3458. The protein was extracted from the extracellular extract by using the ethanol precipitation method. Partial purification of pterin deaminase enzyme was achieved by ion exchange chromatography (Hi-Trap QFF) by fast protein liquid chromatography (AKTA purifier). The molecular weight of the protein was apparently determined by SDS-PAGE, and the presence of pterin deaminase was confirmed by activity staining. The purified enzyme was further biochemically characterized. Molecular docking studies showed higher binding affinity towards folic acid interaction. The structural characterization of this protein may open the windows for new drug targets for cancer therapy.