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In the model cyanobacteriumSynechocystissp. PCC 6803, the terminalenzyme of chlorophyll biosynthesis, chlorophyll synthase (ChlG), forms acomplex with high light-inducible proteins, the photosystem II assembly fac-tor Ycf39 and the YidC/Alb3/OxaI membrane insertase, co-ordinatingchlorophyll delivery with cotranslational insertion of nascent photosystempolypeptides into the membrane. To gain insight into the ubiquity of thisassembly complex in higher photosynthetic organisms, we produced functionalforeign chlorophyll synthases in a cyanobacterial host. Synthesis of algal andplant chlorophyll synthases allowed deletion of the otherwise essential nativecyanobacterial gene. Analysis of purified protein complexes shows that theinteraction with YidC is maintained for both eukaryotic enzymes, indicatingthat a ChlG-YidC/Alb3 complex may be evolutionarily conserved in algaeand plants.

Background & objectives: Dengue (DEN) is a rapidly spreading arboviral disease transmitted by Aedes mosquitoes. Although it is endemic in India, dengue virus (DENV) infection has not been reported from tribal areas of Madhya Pradesh. Investigations were conducted to establish the aetiology of sudden upsurge of cases with febrile illness in June 2013 from tribal villages of Mandla district of Madhya Pradesh, India. Methods: The rapid response team of the National Institute for Research in Tribal Health, Jabalpur, conducted clinical investigations and field surveys to collect the samples from suspected cases. Samples were tested using molecular and serological tools. Collected mosquitoes were identified and tested for the presence of virus using semi nested reverse transcriptase-polymerase chain reaction (nRT-PCR). The sequences were analysed to identify serotype and genotype of the virus. Results: Of the 648 samples collected from 18 villages of Mandla, 321 (49.53%) were found to be positive for dengue. The nRT-PCR and sequencing confirmed the aetiology as dengue virus type 2. Eighteen per cent of patients needed hospitalization and five deaths were attributed to dengue. The virus was also detected from Aedes aegypti mosquito, which was incriminated as a vector. Phylogenetic analysis revealed that the dengue virus 2 detected belonged to cosmopolitan genotype of the virus. Interpretation & conclusions: Dengue virus serotype 2 was detected as the aetiological agent in the outbreak in tribal villages of Mandla district of Madhya Pradesh. Conducive man-made environment favouring mosquitogenic conditions and seeding of virus could be the probable reasons for this outbreak. Urgent attention is needed to control this new threat to tribal population, which is already overburdened with other vector borne diseases.

Hepatitis A virus (HAV) infection, a major cause of childhood hepatitis is transmitted by orofaecal route. Children mostly suffer with subclinical infection but may have serious clinical implications leading to hospitalization and mortality. IgM ELISA and nRT PCR were conducted on the blood samples collected from HAV suspected paediatric cases referred to the viral diagnostic laboratory in the Regional Medical Research Centre for Tribals at Jabalpur, Central India. The nRT PCR products were sequenced and phylogenetic analysis was done. o0 f the 195 samples tested, 41 (21%) were positive for HAV antibodies, among which 38 (92%) belonged to paediatric age group and 32 per cent of these were hospitalized. nRT PCR and sequencing confirmed the presence of HAV. Phylogenic analysis revealed circulation of genotype III A in central India. Regular serological and molecular monitoring would aid in understanding epidemiology of HAV and plan intervention strategies.