Estrone degrading enzymes of Spirulina CPCC-695 and synthesis of bioplastic precursor as a by-product.

Estrone, a steroidal estrogen that is persistently contaminating the surface water has been classified as an endocrine disruptor and as Group-1 carcinogen by the World Health Organization. Long-term exposure to estrone-contaminated water disrupt physiology, behaviour and sexual development of living organisms that lead to many disorders. So, it has to be eliminated from our surrounding. Its biological degradation is a cost effective and eco-friendly approach. The present study targets to predict the degradation pathway and understand the role of cyanobacterial enzymes: oxidoreductases (laccase, peroxidase) and esterase in estrone degradation. Poly-ß-hydroxy butyrate (PHB) was also quantified as a by-product of estrone biodegradation. The estrone degradation pathway was predicted using EAWAG-BBD/PPS database. Spirulina CPCC-695 was grown in different concentration of estrone (20 mg/l, 50 mg/l, 100 mg/l and 200 mg/l). The culture without estrone was considered as control. The culture supernatant was used for testing laccase and esterase activity whereas the biomass was used to test peroxidase activity and quantify by-product (PHB). The enzymes showed concentration-dependent activities. Maximum enzyme activities were seen at 20 mg/l estrone. Spirulina CPCC-695 utilizes estrone as a carbon source and degrades it to produce pyruvate which forms acetyl CoA that undergo condensation, reduction and polymerization to form PHB. Maximum PHB (169 µg) was also produced at 20 mg/l as a by-product during degradation.

Genotypes of glycoprotein B gene among the Indian symptomatic neonates with congenital CMV infection.

BACKGROUND: Cytomegalovirus [CMV] is a causative agent of congenital infection worldwide and often leads to neurological deficits and hearing loss in newborns. Infants born with symptomatic congenital Cytomegalovirus infection [cCMV] are at significant high risk for developing adverse long-term outcomes. In this study, we look into the sequence variability of surface glycoprotein B [gB] encoding region in newborns with symptomatic CMV infection for the first time in Eastern region of India. METHODS: 576 suspected newborns from seropositive mothers were subjected to the study and ELISA was used to confirm CMV infection. Different genotypes and their subtypes were determined using multiplex nested-PCR. Viral load of different glycoprotein B [gB] genotypes was measured using RT-PCR. Sequencing and phylogenetic analysis was then performed using Bayesian interference. RESULTS: The overall frequency of cCMV infection was 18.4%, where 16.0% neonates were symptomatic. Among the different gB genotypes, gB1 had the highest frequency [23.5%] and gB4 showed the lowest occurrence [5.8%]. 23.5% of symptomatic neonates had mixed genotypes of gB, probably indicating matrenal reinfection with CMV strains in Indian population. Significant genotypic clades [gB1-gB2-gB3-gB5] were grouped closely based on gene sequences, but the gB4 sequence was in the outlier region of the phylogenetic tree indicating the genetic polymorphism. CONCLUSION: This is the first study on cCMV genotyping and its phylogenetic analysis from Eastern Indian neonatal population. The study holds importance in the assessment of cCMV seroprevalence in global perspective. gB protein can be used as a potential therapeutic target against CMV infection.

Carbaryl stress induced cellular changes in Calothrix brevissima.

Cyanobacterial biofertilizers are affected by paddy field pesticides as nontarget organism. Carbaryl is a carbamate pesticide and is commonly used against rice thrip pest in paddy fields. In the present work, cellular changes caused by exposure of the cyanobacterial biofertilizer namely Calothrix brevissima to carbaryl were studied with special reference to fatty acids, electrolyte leakage, sulfur metabolism, and osmolytes. To study the toxic effect of carbaryl, the test cyanobacterium was exposed to varying concentrations of pesticide (0, 10, 20, 30, and 40 mg L(-1)) for biochemical analyses. At 40 mg L(-1) carbaryl, polyunsaturated fatty acids were reduced by 32 % and membrane leakage was increased by 27 % suggesting that free radical-mediated lipid peroxidation took place. The sulfur-containing metabolites namely cysteine, cystine, and methionine were increased by 79, 64, and 52 %, respectively. The enzymatic and nonenzymatic antioxidants namely glutathione S-transferase, glutathione reductase, reduced glutathione, and oxidized glutathione were increased to 56, 71, 72, and 60 %, respectively. Osmolytes that serve as stress enzyme protectors as well as nonenzymatic free radical scavenger were also increased, indicating their protective nature in context with carbaryl-induced stress. The respective increase in mannitol, trehalose, and glycogen were 158, 98, and 159 %. In C. brevissima, carbaryl-induced membrane leakage was counteracted by increasing enzymatic and nonenzymatic parameters that helped in scavenging free radicals.