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Background: Methicillin resistant Staphylococcus aureus (MRSA) refers to a group of gram-positive bacteria that are genetically distinct from other strains of Staphylococcus aureus that has developed, through horizontal gene transfer, natural selection and multiple drug resistance to beta lactam antibiotics and thus causing many severe diseases which are very problematic to treat as they are resistant to different antibiotics. The above situation is further aggravated by the formation of biofilms which are structured aggregation of surface attached microbes encased in an extracellular matrix. Thus, the time required to develop biofilms becomes an important point to study. Methods: In the present study, detection of the extent of biofilm formation by MRSA isolates, was performed using the Microtitre Plate Assay. The test was performed in triplicates and was continued for a time period of 7 days to detect the extent of biofilm formation with increase in incubation interval. Result: On comparing the biofilm forming ability of different isolates from Day 1 to Day 7, it could be clearly observed that the biofilm forming capacity of isolates gradually increased with increase in incubation time and most of the isolates became strong biofilm producers from Day 4.

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Background: Mastitis is mostly caused by mixed infections, of which S. aureus and E. coli are amongst the most important bacteria. Detection of resistant strains of these bacteria is a major public health concern due to the possibility of infection via contaminated milk and milk products intended for human consumption. This study describes simultaneous occurance of methicillin-resistant S. aureus and extended spectrum β-lactamase producing E. coli in mastitic milk samples of buffaloes in Jabalpur, India. Methods: A total of 408 buffaloes milk samples were screened for mastitis by California mastitis test (CMT) test. A total of 102 mastitic milk samples were collected for isolation of Staphylococcus aureus (S. aureus) and Eschirichia coli (E. coli). Polymerase chain reaction was performed for molecular characterization of methicillin resistant S. aureus for mecA gene and ESBL producing E. coli for bla TEM gene, respectively. Result: On the basis of cultural and biochemical characteristics, 31/102 samples yielded S. aureus and 10/102 samples yielded E. coli. Out of 31 S. aureus isolates, mecA gene was positive in 05 (16.1%) and out of 10 ESBL producing E. coli isolates bla TEM was positive in 02 (20%) isolates. Coexpression of bla TEM and mecA genes was recorded only in 01 (10%) isolate.

Background: The present study was aimed at cloning and expression of the major outer membrane porin (ompH) gene of P. multocida serotype B:2 P52, the strain used in vaccines against HS in India. The Porin H (OmpH) is major immunodominant outer membrane protein in the envelope of Pasteurella multocida. Methods: The gene encoding OmpH was amplified by PCR, cloned and expressed in prokaryotic expression vector. The recombinant OmpH protein was expressed as a protein with E. coli BL21 (DE3) cells transformed with recombinant plasmid pQE30-Xa-ompH. Result: The expressed protein was purified from E. coli and characterized by SDS-PAGE and western blot analysis. The fusion recombinant protein eluted had a molecular mass of about 34 kDa. The expressed recombinant protein was confirmed with western blot analysis using RGS-His antibody and anti-P. multocida serum raised against whole cell lysate.