Agrobacterium-mediated transformation protocol to overcome necrosis in elite AustralianBrassica juncea lines

In recent years,Brassica species have acquired an important position in the oilseed industry. Even thoughBrassica transformation protocols are well established,there is still a need for the development of new transformation protocols for elite AustralianB. juncea lines,because regeneration inB. juncea is highly genotype-dependent and in addition, their hypocotyl explants are susceptible to necrosis.Agrobacterium-mediated transformation protocol to overcome necrosis in elite AustralianB. juncea lines is described here. To overcome necrosis, we have adopted 2 strategies: extension of precultivation time of hypocotyl explants, and use of a 2-stage hygromycin selection process.The frequency of recovery of transformants from AustralianB. juncea andBrassica napus lines was 1.7% and 0.9%, respectively. Polymerase chain reaction tests confirmed that allBrassica plants that survived through stringent screening procedures were positive for the inserted hygromycin resistance gene,hph. Progeny from 6Brassica lines tested segregated for thehph gene, and χ² analysis suggested a 3:1 segregation ratio.This is in line with a tDNA integration into a single locus, which is an important feature of a transformation protocol for subsequent breeding purposes. Although the scientific content of this article has been reviewed,the full-text Web publication has not been edited in detail.     

A Novel Calcium Oxalate Crystal Growth Inhibitory Protein from the Seeds of Dolichos biflorus (L.)

Recurrence and persistent side effects of present day treatment for urolithiasis restrict their use, so an alternate, using phytotherapy is being sought. Dolichos biflorus seeds, which are used as dietary food in India, possess antilithiatic properties. In the present study, a novel dimeric antilithiatic protein (98 kDa) from its seeds was purified based on its ability to inhibit calcium oxalate crystallization in vitro. Amino acid analysis of Dolichos biflorus antilithiatic protein showed abundant acidic amino acids. The mascot search engine presented sequence similarity with a calcium binding protein, calnexin of Pisum sativum from the m/z data obtained by MALDI TOF mass spectrometer. Above results demonstrate the anticalcifying/antilithiatic nature of a novel protein from the seeds of Dolichos biflorus and thus open new vistas for using plant proteins as therapeutic agents to treat urolithiasis.     

Human immune response to monoclonal antibody-enzyme conjugates in ADEPT pilot clinical trial

The human immune response to monoclonal antibody-enzyme conjugates has been studied in patients included in the pilot clinical trial of ADEPT. Each patient received murine monoclonal anti-CEA antibody fragments (A5B7-F(ab')2, conjugated to bacterial enzyme, carboxypeptidase G2 (CPG2) followed by a galactosylated monoclonal anti-CPG2 antibody (SB43), 36–48 h after the conjugate. Some patients were also given a dose of¹³¹I-labeled conjugate (4–8 mg, 7–15 mCi) for blood clearance and gamma camera image studies. All patients studied developed human antimouse antibodies (HAMA) and anti-CPG2 antibodies within 10 d after a single course of treatment with the conjugate. In most cases, IgM response was detected at 7 d after the conjugate followed by the IgG response 14 d later. In one patient, HAMA and anti-CPG2 antibodies of the IgG type could still be detected at 10 mo after treatment. Anti-CPG2 antibodies in serum of one patient were found to inhibit CPG2 activity in vitro. Generation of neutralizing antibodies limits the use of repeat cycles of ADEPT in patients. Use of immunosuppressive agents may allow a useful time window for several ADEPT cycle treatments by delaying the appearance of HAMA and anti-CPG2 antibodies. Patients given cyclosporin A before and during ADEPT are currently being studied for HAMA and anti-CPG2 response.     

Recent trends in biological extraction of chitin from marine shell wastes: a review

The natural biopolymer chitin and its deacetylated product chitosan are widely used in innumerable applications ranging from biomedicine, pharmaceuticals, food, agriculture and personal care products to environmental sector. The abundant and renewable marine processing wastes are commercially exploited for the extraction of chitin. However, the traditional chitin extraction processes employ harsh chemicals at elevated temperatures for a prolonged time which can harm its physico-chemical properties and are also held responsible for the deterioration of environmental health. In view of this, green extraction methods are increasingly gaining popularity due to their environmentally friendly nature. The bioextraction of chitin from crustacean shell wastes has been increasingly researched at the laboratory scale. However, the bioextraction of chitin is not currently exploited to its maximum potential on the commercial level. Bioextraction of chitin is emerging as a green, cleaner, eco-friendly and economical process. Specifically in the chitin extraction, microorganisms-mediated fermentation processes are highly desirable due to easy handling, simplicity, rapidity, controllability through optimization of process parameters, ambient temperature and negligible solvent consumption, thus reducing environmental impact and costs. Although, chitin production from crustacean shell waste through biological means is still at its early stage of development, it is undergoing rapid progress in recent years and showing a promising prospect. Driven by reduced energy, wastewater or solvent, advances in biological extraction of chitin along with valuable by-products will have high economic and environmental impact.