ABSTRACT
In the current study, we analyzed the efficacy of manganese oxide nanoparticle (MnNP)-water dispersion as an immobilization matrix for bacterial tannase. The tannase-secreting Bacillus subtilis strain NJKL.tan.2 obtained from tannery effluent soil was subsequently purified and cloned in pET20b vector. The activity of MnNP-tan (tannase activated by manganese nanoparticles) was 1.51- and 3.5-fold higher at 20 °C and 80 °C, respectively, compared with the free enzyme. MnNP-tan decreased Km by 41.66 % and 3-fold, whereas free tannase showed two-fold and six-fold improvement in Kcat at 37 °C and 80 °C, respectively. MnNP-tan showed an increase in (half-life)t1/2and Ed by 13-fold and 50.05 units, respectively, at 80 °C, in contrast to the native enzyme. MnNP-tan retained its residual activity by 78.2 % at 37 °C and 34.24 % at 80 °C after 180 min of incubation when compared with untreated set. MnNP-tan retained 51 % of its activity after 120 days with the native enzyme losing â¼50 % functionality following 40 days of incubation. The MnNP-mediated tannase immobilization technique is being reported for the first time. The technique has numerous advantages due to the use of MnNP as a potential matrix for biomolecule immobilization, which can be further extended to immobilize other biocatalysts used in agro-industrial and lab-based applications.
Subject(s)
Carboxylic Ester Hydrolases , Manganese , Nanoparticles , Bacillus subtilis , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/genetics , Enzymes, Immobilized , Hydrogen-Ion Concentration , IonsABSTRACT
No study in the past has examined the genetic diversity and zoonotic potential of Giardia duodenalis in dairy cattle in India. To assess the importance of these animals as a source of human G. duodenalis infections and determine the epidemiology of bovine giardiasis in India, fecal samples from 180 calves, heifers and adults and 51 dairy farm workers on two dairy farms in West Bengal, India were genotyped by PCR-RFLP analysis of the ß-giardin gene of G. duodenalis followed by DNA sequencing of the nested PCR products. The overall prevalence of G. duodenalis in cattle was 12.2% (22/180), the infection being more prevalent in younger calves than in adult cattle. Zoonotic G. duodenalis Assemblage A1 was identified in both calves and workers although the most prevalent genotype detected in cattle was a novel Assemblage E subgenotype. These findings clearly suggest that there is a potential risk of zoonotic transmission of G. duodenalis infections between cattle and humans on dairy farms in India.
Subject(s)
Cattle Diseases/parasitology , Giardia/isolation & purification , Giardiasis/veterinary , Zoonoses/parasitology , Animals , Base Sequence , Cattle , Cattle Diseases/transmission , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Feces/parasitology , Female , Genetic Variation , Giardia/genetics , Giardiasis/parasitology , Giardiasis/transmission , Humans , India , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/veterinary , Polymorphism, Restriction Fragment Length , Sequence Alignment , Zoonoses/transmissionABSTRACT
Few studies in the past have examined the genetic diversity and zoonotic potential of Cryptosporidium in dairy cattle in India. To assess the importance of these animals as a source of human Cryptosporidium infections, fecal samples from 180 calves, heifers and adults and 51 farm workers on two dairy farms in West Bengal, India were genotyped by PCR-RFLP analysis of the 18S rRNA gene of Cryptosporidium followed by DNA sequencing of the PCR products. Phylogenetic analysis was carried out on the DNA sequences obtained in the study and those available in GenBank. The overall prevalence of Cryptosporidium in cattle was 11.7% though the infection was more prevalent in younger calves than in adult cattle. The occurrence of Cryptosporidium parvum, Cryptosporidium bovis, Cryptosporidium ryanae and Cryptosporidium andersoni in cattle followed an age-related pattern. A Cryptosporidium suis-like genotype was also detected in a calf. Farm workers were infected with Cryptosporidium hominis, C. parvum and a novel C. bovis genotype. These findings clearly suggest that there is a potential risk of zoonotic transmission of Cryptosporidium infections between cattle and humans on dairy farms in India.
