title: Heavy metal pollution exerts reduction/adaptation in the diversity and enzyme expression profile of heterotrophic bacteria in Cochin estuary, India.
abstract: Over the past three decades heavy metal pollution has increased substantially in Cochin estuary, south west coast of India. Here we studied the distribution, diversity and enzyme expression profile of culturable microbial population along a pollution gradient. The distribution of resistance against 5 mM concentration of Zn, Co, Ni and Cu was observed among 90-100% of bacterial isolates retrieved from highly polluted Eloor, whereas it was less than 40% in Vypin and Munambam. Similarly, there was a difference in the distribution and diversity of bacterial phyla with predominance of Proteobacteria in Eloor and Firmicutes in Munambam and Vypin. We observed that 75-100% of the organisms retrieved from Eloor had low levels of expression for hydrolytic enzyme. In conclusion, the heavy metal pollution in Cochin estuary brought in reduction/adaptation in the distribution, diversity and enzyme expression profile of bacteria, which may impart adverse impacts on ecosystem functioning.
authors.affiliation: National Institute of Oceanography, CSIR, Regional Centre, PB 1913, Cochin, Kerala 682018, India.
authors.forename: Jiya
authors.initials: J
authors.lastname: Jose
authors.forename: Rajesh
authors.initials: R
authors.lastname: Giridhar
authors.forename: Abdulaziz
authors.initials: A
authors.lastname: Anas
authors.forename: P A
authors.initials: PA
authors.lastname: Loka Bharathi
authors.forename: Shanta
authors.initials: S
authors.lastname: Nair
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D001419:Bacteria / Q000145:classification / Q000187:drug effects* / Q000201:enzymology; D018407:Bacterial Physiological Phenomena / Q000187:drug effects; D044822:Biodiversity; D017753:Ecosystem; D005618:Fresh Water / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry; D052836:Heterotrophic Processes; D007194:India; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity*; D012623:Seawater / Q000737:chemistry; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical