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The immunoglobulin (Ig) binding proteins of Staphylococcus aureus namely staphylococcal protein A (SpA) and staphylococcal binder of immunoglobulin (Sbi) are responsible for false positives during immunoassays. Avian IgY antibodies were reported to have no affinity to SpA and thus are safe for use in immunoassays. However, the behaviour of Sbi with IgY was not reported. The purpose of the present study is to evaluate the interactions between IgY antibodies and Sbi protein from different S. aureus strains. Initially, heterologous cloning and expression of complete sbi gene in Escherichia coli was undertaken. Recombinant Sbi protein was utilized to generate polyclonal anti-Sbi IgY and anti-Sbi antibodies in chicken and BALB/c mice respectively. Indirect ELISA and Western blotting were performed to evaluate the reactivity of anti-Sbi antibodies. Non-reducing PAGE followed by Western blotting and double-antibody sandwich dot-ELISA were performed to analyze the reactivity of IgY antibodies with recombinant Sbi and native Sbi from S. aureus strains. To avoid the possible interference of enzyme-conjugated secondary antibodies from mammalian sources, mouse anti-Sbi revealing antibodies were labeled with biotin so that streptavidin-HRP was used as developing reagent for chromogenic reaction. Sbi was highly immunogenic in chicken and mouse with antibody titers of 1:128,000 and 1:64,000 dilutions respectively. We observed that unimmunized IgY antibodies showed no affinity to either recombinant Sbi or native Sbi from S. aureus strains in Western blotting and double antibody sandwich ELISA. In view of these observations, we recommend that IgY antibodies are safe and free from false positives due to SpA and Sbi in immunoassays involving detection of S. aureus antigens/exotoxins.

A novel approach of cellulase-based co-culture producing bioethanol using low-cost nutrient medium has been employed for the study, and docking strategies provided the information of cellobiose and cellotetraose inhibitors during cellulase production. The Acinetobacter species was isolated from termite gut and confirmed in 16s rDNA analysis. SDS-PAGE reveals the molecular weight of purified cellulose was 45 kDa. Cellulose activity was achieved maximum of 1.2 IU/mL at 48th hour of incubation, and about 80% of polysaccharides were converted into simple sugars. The enzyme activity was optimum at different physiological conditions like temperature at 37 °C, pH 7.0 and with 4% concentration of banana peduncle extract powder. Upon reaching maximum cellulolytic activity of 0.594 IU/mL, the percentage of ethanol produced from cellulosic hydrolysate using S. cerevisiae reached maximum ethanol (18.3 g/L) during 48 h of incubation. Cellulase produced by Acinetobacter indicus KTCV2 strain exhibits a short incubation period (48 h) and produces cellulase in broader pH and temperature ranges. Banana peduncle offers a cheapest raw material composed of cellulosic biomass in agricultural practices, which served as a good substrate for the production of ethanol.

Freshwater biota especially molluscs are more vulnerable because even the slightest change in the quality of their habitat possibly leads to their mortality. In addition, their importance is felt that particularly molluscs contribute toward carbon sequestering from the environment as atmospheric carbon gets deposited as carbonates in their shell which constitute 10% of their body mass. Hence, the molecular phylogenetic relationships of two families inhabiting freshwater streams viz., Ampullariidae and Viviparidae considering the genera dwelling in Indian subcontinent namely Pila globosa and Bellamya bengalensis using the partial nucleotide sequence of mitochondrial COI gene were of considerable importance in building conservational strategies. The phylogenetic analysis of ampullariid and viviparid species inferred that these two chosen families were paraphyletic and rooted on the genera of Cyclophoroidea and possibly with Saulea vitrea as the connecting link.

Background ATP-binding cassette (ABC) transporters constitute one of the largest transporter protein families and play a role in diverse biological processes. Results In the present study, bacteriocin isolated from the Enterococcus casseliflavus MI001 strain was identified as an ABC transporter ATP-binding protein. The optimal conditions for the production of bacteriocin were found to be at 35 °C, a pH 5.5, and an incubation time of 24 h. Purification was performed using ammonium sulphate precipitation, gel filtration, and DEAE ion exchange chromatography. The bacteriocin was purified with an eightfold purification scheme resulting with a specific activity of 15,000 AU/mg. The NMR spectrum of purified bacteriocin revealed the presence of amino acids, namely lysine, methionine, cysteine, proline, threonine, tryptophan, and histidine. Further, the bacteriocin ABC transporter showed antimicrobial activity against food spoilage microorganisms. Conclusions The ABC transporter ATP-binding protein could be used as a potential alternative for food preservation, and it may be considered as a bio-preservative agent in food processing industries.

In the present work, a simple and straightforward method was developed to clone any PCR-amplified products into restriction sites that are very close, adjacent or overlapping in the expression vector. The novelty of the methodology involves a crucial primer-designing step by adding appropriate overhangs to the 5' ends of primers based on the multiple cloning sites (MCS) (polylinker) region of expression vector. After PCR amplification, actual cloning is performed not in adjacent RE sites, but in sites that are little distant in the MCS. However, the sites lost during this cloning step are maintained intact since they are provided by the cloned PCR product (through the primer overhangs). Gene for green fluorescent protein (GFP) was cloned and expressed employing this strategy to demonstrate its simplicity. This method is highly useful for vector modification without losing the restriction sites present in the MCS.

There is an increasing demand for the generation of recombinant pharmaceutical proteins for a wide array of therapeutic applications. In comparison to bacterial, yeast and animal cells, the production of recombinant proteins in plants with economic and therapeutic importance has only started recently. The most important prerequisite of any expression systems is that it should be simple and inexpensive. In this regard, plant-based expression has emerged an as accepted alternative to conventional expression platforms due to economic feasibility, rapid scalability, higher stability of recombinant proteins, safety due to lack of harmful substances (human, animal pathogens and pyrogens) and capability of producing proteins with desired secondary modifications. Heterologous expression using plants has played a pivotal role in the development of a myriad of recombinant proteins, including neutraceuticals and monoclonal antibodies being utilized in various therapeutic approaches. This paper presents an overview about the current status, various strategies and advantages of pharmaceutical protein production in plant expression systems. We also present a summary of expression of therapeutic monoclonal antibodies, vaccines, clinical trials and the regulatory aspects of plant-based expression. Furthermore, the challenges encountered in plant expression such as costs associated with existing purification strategies are discussed.