Avian metapneumovirus (aMPV), also known as avian pneumovirus or turkey rhinotracheitis virus, is the causative agent of turkey rhinotracheitis and is associated with swollen head syndrome in chickens. Since its discovery in the 1970s, aMPV has been recognized as an economically important pathogen in the poultry industry worldwide. The conserved region VI (CR VI) of the large (L) polymerase proteins of paramyxoviruses catalyzes methyltransferase (MTase) activities that typically methylate viral mRNAs at guanine N-7 (G-N-7) and ribose 2=-O positions. In this study, we generated a panel of recombinant aMPV (raMPV) Colorado strains carrying mutations in the S-adenosyl methionine (SAM) binding site in the CR VI of L protein. These recombinant viruses were specifically defective in ribose 2=-O, but not G-N-7 methylation and were genetically stable and highly attenuated in cell culture and viral replication in the upper and lower respiratory tracts of specific-pathogen-free (SPF) young turkeys. Importantly, turkeys vaccinated with these MTase-defective raMPVs triggered a high level of neutralizing antibody and were completely protected from challenge with homologous aMPV Colorado strain and heterologous aMPV Minnesota strain. Collectively, our results indicate (i) that aMPV lacking 2=-O methylation is highly attenuated in vitro and in vivo and (ii) that inhibition of mRNA cap MTase can serve as a novel target to rationally design live attenuated vaccines for aMPV and perhaps other paramyxoviruses. IMPORTANCE Paramyxoviruses include many economically and agriculturally important viruses such as avian metapneumovirus (aMPV), andNewcastle disease virus (NDV), human pathogens such as human respiratory syncytial virus, human metapneumovirus, human parainfluenza virus type 3, and measles virus, and highly lethal emerging pathogens such as Nipah virus and Hendra virus. For many of them, there is no effective vaccine or antiviral drug. These viruses share common strategies for viral gene expression and replication. During transcription, paramyxoviruses produce capped, methylated, and polyadenylated mRNAs. Using aMPV as a model, we found that viral ribose 2=-O methyltransferase (MTase) is a novel approach to rationally attenuate the virus for vaccine purpose. Recombinant aMPV (raMPV) lacking 2=-O MTase were not only highly attenuated in turkeys but also provided complete protection against the challenge of homologous and heterologous aMPV strains. This novel approach can be applicable to other animal and human paramyxoviruses for rationally designing live attenuated vaccines.

Hedera nepalensis is commonly used in folk medicines for the treatment of cough and other human ailments; therefore it was selected for phytochemical and antimicrobial screening. Its phytochemical screening showed the presence of different classes of secondary metabolites. The ethyl acetate extract of its stem showed the presence of steroids, terpenoids, saponins and flavonoids. Terpenoids and flavonoids were present in chloroform and ethyl acetate fractions, steroids were present in chloroform and ethyl acetate crude extract. Ethyl acetate and chloroform fractions were found most active. Among the organisms tested, Escherichia coli was the most sensitive to the plant extract as it displayed the greatest inhibitory zone (20:0 mm).

The antimicrobial potentiality of Polyalthia longifolia seed oil and its fatty acid methyl ester (FAME) extract was evaluated against multi drug resistant strains of bacteria and fungi of clinical origin. A sensitivity test was performed to determine the resistance pattern for marketed antimicrobial agents against the selected microorganisms. The results of antimicrobial assay revealed that P. longifolia seed oil and its FAME extract were effective against all the microorganisms studied. Enterococcus faecalis, Streptococcus mutans and Streptococcus bovis were observed to be the most susceptible strains. Among the tested Gram-negative bacteria, Klebsiella pneumoniae was found to be the most sensitive, while Salmonella typhimurium was the most resistant bacteria. In the case of Gram-positive bacteria, E. faecalis was the most sensitive, while S. aureus was the most resistant strain. The Candida albicans was found to be highly sensitive to the action of FAME extract with the least minimum inhibitory concentration (MIC) of 19.5 µg/ml. The MIC values were lower than MBC/MFC values suggesting that the P. longifolia seed oil and its FAME extract inhibit the growth of test organisms while being bactericidal/fungicidal at higher concentrations. In addition, the physiochemical properties and fatty acid composition of P. longifolia seed oil were also investigated. Thus, it was found that P. longifolia seed oil offers potential antibacterial property against the reference strains and could be a possible source to obtain new and effective herbal medicines to treat infections caused by multi-drug resistant strains of microorganisms from community as well as hospital settings.

Two different strains of Rhizopus sp. i.e. R. oligosporus-M30 and R. arrhizus-M26 were employed for the production of acid protease using different agro-residues such as rice husk, rice bran, wheat bran, defatted soybean meal and sunflower meal as a sole carbon source. R. oligosporus-M30 gave maximum enzyme level with soybean meal (15.6 U/gds) while R. arrhizus-M26 with sunflower meal (13.6 U/gds) respectively. The optimal conditions for the enzyme production by R .oligosporus-M30 were initial pH of 5.5, temperature 30 o C with 10% of inoculum size for 72hr of fermentation period. When R. arrhizus-M26 was cultivated that exhibit the best enzyme production with the fermentation period of 72h, initial pH 5.0, temperature 33 o C with 5% of inoculum size

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