Identification and characterization of psychrotrophic strain of Planococcus maritimus for glucosylated C30 carotenoid production

Abstract

Cold-adapted bacteria produce various pigments as their adaptive strategy. Here, we studied an aerobic, gram-positive motile coccoid bacterial strain KK21, isolated from the Siachen, Himalayas and characterized the major pigments present in it. The KK21 strain is capable of growth in a broad range of temperature (-4 to 37°C), pH (6.0-13.0) and salinity (0.5-8%). Phylogenetic analysis based on 16S rRNA gene sequence showed that it belongs to the genus Planococcus and closely related to P. maritimus. Total pigment extraction was best found in polar methanol. Alanine among amino acids, NaCl among inorganic salts and evening primrose amongst oils best supported the pigment production at 10°C after 6 days in BHI at neutral pH of 7.0. Maximum pigment production was recorded at 3% of NaCl concentration. In photoprotection activity, radiation exposed plates showed increased colony forming units and more than 3.5 times of total carotenoid production after 15 min exposure compared to the control group. Detailed characterization of orange pigment was done systematically by TLC, HPLC and MALDI-TOF. Chromatographic and MALDI-TOF data have revealed the exclusive presence of glycosylated C₃₀-carotenoid in P. maritimus KK21 with m/z of 655.871.