RESUMO

Canine adenoviruses (CAVs) are of two types: canine adenovirus type 1 (CAV-1), which causes infectious canine hepatitis, and canine adenovirus type 2 (CAV-2), which is mainly associated with the respiratory type of disease in dogs. Due to the widespread use of modified live vaccines to control canine adenoviral infections and subsequently reduced disease incidence, CAVs are often neglected by clinicians. Although a number of studies are available about CAV-1 prevalence in India, only meagre information is available about CAV-2. This study reports the CAV-2 infection in a vaccinated dog with neurological and respiratory symptoms which was found negative for other canine pathogens like canine distemper virus and canine parvovirus. The virus was successfully isolated from rectal swab in MDCK cells and characterized by immunofluorescence assay and virus neutralization test. On phylogenetic analysis of partial E3 region, the Indian CAV-2 grouped in a separate clade different from established subgroups. An insertion of "G" nucleotide was reported at nucleotide (nt.) position 1077 in the E3 gene of Indian CAV-2 isolates which led to a frameshift in the coding region of E3 gene thereby imparting additional eleven amino acids to its C-terminal end in comparison to isolates from other parts of the world. This may have an implication on the functional role of E3 protein inside the cell. This study reinforces the unique signature insertion in the E3 gene of Indian CAV-2 and is the second study in the world to report the association of CAV-2 with neurological disease in dogs.

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RESUMO

A purificação de uma etapa e caracterização de uma xilanase livre de celulase de uma linhagem recentemente isolada alcalofílicos e moderadamente termofílico de Bacillus subtilis ASH. Xilanase foi purificada à homogeneidade de 10,5 vezes, com ~ por cento de recuperação 43 através de cromatografia de troca iônica através de CM- Sephadex C -50. A enzima purificada revelou uma única banda no gel SDS-PAGE com uma massa molecular de 23 kDa. Ele mostrou um pH ótimo de 7,0 e manteve-se estável na faixa de pH 6,0-9,0 . A temperatura ótima para atividade da enzima foi 55 º C. A xilanase purificada não perder nenhuma atividade até 45 º C , no entanto, manteve 80 por cento e 51 por cento de sua atividade após pré-incubação a 55 º C e 60 º C , respectivamente. A enzima obedecido Michaelis- Menton cinética para xilano de madeira de bétula com aparente km 3,33 mg / ml e Vmax 100 UI / ml. A enzima foi fortemente inibida por Hg2 +, Cu2 + , enquanto reforçada por Co2 + e Mn2 +. A enzima purificada pode ser armazenado a 4 º C por seis semanas sem nenhuma perda de atividade catalítica. A purificação mais rápido e econômico da xilanase livre de celulase de B. subtilis ASH por um passo-a processo juntamente com a sua estabilidade sensível a alta temperatura e pH alcalino torna potencialmente eficazes para aplicações industriais.

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RESUMO

The present study describes the one-step purification and characterization of an extracellular cellulase-free xylanase from a newly isolated alkalophilic and moderately thermophilic strain of Bacillus subtilis ASH. Xylanase was purified to homogeneity by 10.5-fold with ~43% recovery using ion-exchange chromatography through CM-Sephadex C-50. The purified enzyme revealed a single band on SDS-PAGE gel with a molecular mass of 23 kDa. It showed an optimum pH at 7.0 and was stable over the pH range 6.0-9.0. The optimum temperature for enzyme activity was 55 °C. The purified xylanase did not lose any activity up to 45 ºC, however, it retained 80% and 51% of its activity after pre-incubation at 55 ºC and 60 ºC, respectively. The enzyme obeyed Michaelis-Menton kinetics towards birch wood xylan with apparent Km 3.33 mg/ml and Vmax 100 IU/ml. The enzyme was strongly inhibited by Hg(2+)and Cu(2+)while enhanced by Co(2+) and Mn(2+). The purified enzyme could be stored at 4 ºC for six weeks without any loss of catalytic activity. The faster and economical purification of the cellulase-free xylanase from B. subtilis ASH by one-step procedure together with its appreciable stability at high temperature and alkaline pH makes it potentially effective for industrial applications.

RESUMO

The present study describes the one-step purification and characterization of an extracellular cellulase-free xylanase from a newly isolated alkalophilic and moderately thermophilic strain of Bacillus subtilis ASH. Xylanase was purified to homogeneity by 10.5-fold with ~43% recovery using ion-exchange chromatography through CM-Sephadex C-50. The purified enzyme revealed a single band on SDS-PAGE gel with a molecular mass of 23 kDa. It showed an optimum pH at 7.0 and was stable over the pH range 6.0-9.0. The optimum temperature for enzyme activity was 55 ºC. The purified xylanase did not lose any activity up to 45 ºC, however, it retained 80% and 51% of its activity after pre-incubation at 55 ºC and 60 ºC, respectively. The enzyme obeyed Michaelis-Menton kinetics towards birch wood xylan with apparent Km 3.33 mg/ml and Vmax 100 IU/ml. The enzyme was strongly inhibited by Hg2+ and Cu2+ while enhanced by Co2+ and Mn2+. The purified enzyme could be stored at 4 ºC for six weeks without any loss of catalytic activity. The faster and economical purification of the cellulase-free xylanase from B. subtilis ASH by one-step procedure together with its appreciable stability at high temperature and alkaline pH makes it potentially effective for industrial applications.

RESUMO

The effect of trituration on thermal degradation of lactose (sugar of milk) was studied using a thermogravimetric analyser. A correlation between the rate of degradation with increased potency observed up to 600§C suggests that the vehicle plays an important role in the bioavailability of the drug. Comparison was also made between machine and hand tritured lactose. For lower potencies (up to the 2x) machine triturated lactose was found to degrade faster than hand triturated lactose, whereas at higher potencies hand triturated lactose showed faster degradation as compared to machine triturated lactose (AU)

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