Improvement of qualitative and quantitative traits in cotton under normal and stressed environments using genomics and biotechnological tools: A review.

Due to the increasing demand for high-quality and high fiber-yielding cotton (Gossypium spp.), research into the development of stress-resilient cotton cultivars has acquired greater significance. Various biotic and abiotic stressors greatly affect cotton production and productivity, posing challenges to the future of the textile industry. Moreover, the content and quality of cottonseed oil can also potentially be influenced by future environmental conditions. Apart from conventional methods, genetic engineering has emerged as a potential tool to improve cotton fiber quality and productivity. Identification and modification of genome sequences and the expression levels of yield-related genes using genetic engineering approaches have enabled to increase both the quality and yields of cotton fiber and cottonseed oil. Herein, we evaluate the significance and molecular mechanisms associated with the regulation of cotton agronomic traits under both normal and stressful environmental conditions. In addition, the importance of gossypol, a toxic phenolic compound in cottonseed that can limit consumption by animals and humans, is reviewed and discussed.

Mushroom lectins in biomedical research and development.

Lectins are unique biorecognition proteins which recognize and interact with various cell surface carbohydrates/glycoproteins. These ubiquitous molecules are involved in various cell-cell interactions and can be exploited to analyze cell surface associated interactions and biological functions. Amongst fungi, lectins have been extensively explored from mushrooms as compared to microfungi or yeasts. Lectins from basidiomycetes have diverse features in terms of their physico-chemical characteristics and carbohydrate specificity. A plethora of lectins from genera Aleuria, Agrocybe, Boletus, Pleurotus, Russula, Schizophyllum, Volvariella, etc. exhibit potential applications in biomedical field. The current review summarizes the potential sources and characteristics of mushroom lectins. Potential involvement of mushroom lectin as anticancer, mitogenic, antiviral, antimicrobial, antioxidant and therapeutic agents has been discussed.

Structural aspects and biomedical applications of microfungal lectins.

Lectins are unique biorecognition molecules that identify cell surface carbohydrates/glycoproteins and play significant role in various interactions. They are ubiquitous glycan-specific proteins/glycoproteins of non-immune origin. Amongst microfungi, lectins have been widely reported from aspergilli, penicilli, Fusarium sp., etc., however a plethora of genera still remains unexplored. Microfungal lectins have wide diversity in their haemagglutination and carbohydrate specificity. They also exhibit great variations in their structural organization which influences lectin-glycan interactions. The present review summarizes the sources, characteristics and structural diversity of microfungal lectins. Prospective biomedical applications of microfungal lectins as anticancer, mitogenic, immunomodulatory, antioxidant and therapeutic agents have been discussed extensively.

Purification and characterization of a heterodimeric mycelial lectin from Penicillium proteolyticum with potent mitogenic activity.

In the present study, Penicillium proteolyticum lectin was purified by DEAE-Sepharose chromatography followed by Sephadex G-100 gel filtration chromatography. A sequence of ion-exchange and gel filtration chromatography resulted in 52.30 fold purified lectin with a high yield of 84.21%. The purified P. proteolyticum lectin is a glycoprotein with 2.83% linked carbohydrates. A single band in Native-PAGE, whereas two bands (25.1 kDa and 22.9 kDa) in SDS-PAGE confirmed the heterodimeric nature of the purified lectin. The apparent molecular weight (48 kDa) of P. proteolyticum lectin was further confirmed by gel filtration analysis. Heterodimeric P. proteolyticum lectin was stable within a pH range of 6.5-7.5 and upto a temperature of 30 °C. The lectin activity was strongly inhibited by complex glycoproteins and denaturants. Metal ions are not required for agglutination activity of purified lectin. The lectin showed significant mitogenic response towards mice splenocytes. It exhibited highest mitogenic activity at a concentration of 50 µg/mL. This is a first report on characteristics of purified P. proteolyticum lectin having potent mitogenic potential.

Purification and characterization of a mitogenic lectin from Penicillium duclauxii.

Lectins are proteins/glycoproteins of non-immune origin which interact specifically and non-covalently with carbohydrate moieties on the cell surface. In this study, a lectin was purified from Penicillium duclauxii by ion-exchange chromatography on DEAE-Sepharose and gel filtration chromatography on a Sephadex G-100 column. An overall recovery of 94.11% and 60-fold purification was achieved. The purified lectin had a molecular weight of 54.9 kDa and was found to be heterogeneous as revealed by double band of sub-units with molecular mass of 21.13 kDa and 33.26 kDa, under reducing conditions. It is a glycoprotein with carbohydrate content of 3.95%. Lectin induced haemagglutination of erythrocytes was inhibited strongly by glycoproteins such as bovine submaxillary mucin, porcine stomach mucin and fetuin. The maximum haemagglutinating activity of P. duclauxii lectin was maintained after incubation at a temperature and pH range of 20-35 °C and 6.0-8.0, respectively. The haemagglutinating activity of P. duclauxii lectin was unaffected by EDTA and various metal ions. The purified P. duclauxii lectin exhibited maximum mitogenic activity towards mouse splenocytes at a concentration of 75 µg/mL. This manuscript reports a novel lectin from P. duclauxii with potent mitogenic activity towards mouse splenocytes.

Lectins from red algae and their biomedical potential.

Lectins are unique proteins or glycoproteins of non-immune origin that bind specifically to carbohydrates. They recognise and interact reversibly to either free carbohydrates or glycoconjugates, without modifying their structure. Lectins are highly diverse and widely distributed in nature and have been extensively reported from various red algae species. Numerous red algae species have been reported to possess lectins having carbohydrate specificity towards complex glycoproteins or high-mannose N-glycans. These lectin-glycan interactions further trigger many biochemical responses which lead to their extensive use as valuable tools in biomedical research. Thus, owing to their exceptional glycan recognition property, red algae lectins are potential candidate for inhibition of various viral diseases. Hence, the present report integrates existing information on the red algae lectins, their carbohydrate specificity, and characteristics of purified lectins. Further, the review also reports the current state of research into their anti-viral activity against various enveloped viruses such as HIV, hepatitis, influenza, encephalitis, coronavirus and herpes simplex virus and other biomedical activities such as anti-cancer, anti-microbial, anti-inflammatory, anti-nociceptive and acaricidal activities.

Cyanobacterial lectins characteristics and their role as antiviral agents.

Lectins are ubiquitous proteins/glycoproteins of non-immune origin that bind reversibly to carbohydrates in non-covalent and highly specific manner. These lectin-glycan interactions could be exploited for establishment of novel therapeutics, targeting the adherence stage of viruses and thus helpful in eliminating wide spread viral infections. Here the review focuses on the haemagglutination activity, carbohydrate specificity and characteristics of cyanobacterial lectins. Cyanobacterial lectins exhibiting high specificity towards mannose or complex glycans have potential role as anti-viral agents. Prospective role of cyanobacterial lectins in targeting various diseases of worldwide concern such as HIV, hepatitis, herpes, influenza and ebola viruses has been discussed extensively. The review also lays emphasis on recent studies involving structural analysis of glycan-lectin interactions which in turn influence their mechanism of action. Altogether, the promising approach of these cyanobacterial lectins provides insight into their use as antiviral agents.

Protozoa lectins and their role in host-pathogen interactions.

Lectins are proteins/glycoproteins of non-immune origin that agglutinate red blood cells, lymphocytes, fibroblasts, etc., and bind reversibly to carbohydrates present on the apposing cells. They have at least two carbohydrate binding sites and their binding can be inhibited by one or more carbohydrates. Owing to carbohydrate binding specificity of lectins, they mediate cell-cell interactions and play role in protozoan adhesion and host cell cytotoxicity, thus are central to the pathogenic property of the parasite. Several parasitic protozoa possess lectins which mediate parasite adherence to host cells based on their carbohydrate specificities. These interactions could be exploited for development of novel therapeutics, targeting the adherence and thus helpful in eradicating wide spread of protozoan diseases. The current review highlights the present state knowledge with regard to protozoal lectins with an emphasis on their haemagglutination activity, carbohydrate specificity, characteristics and also their role in pathogenesis notably as adhesion molecules, thereby aiding the pathogen in disease establishment.

Amoebiasis vaccine development: A snapshot on E. histolytica with emphasis on perspectives of Gal/GalNAc lectin.

Amoebiasis/amebiasis is a gastrointestinal infection caused by an enteric dwelling protozoan, Entamoeba histolytica. The disease is endemic in the developing world and is transmitted mainly via the faecal-oral route (e.g., in water or food) and may or may not be symptomatic. This disease of socio-economic importance worldwide involves parasite adherence and cytolysis of human cells followed by invasion that is mediated by galactose-binding (Gal/GalNAc) surface lectin. Disruption of the mucus layer leads to invasive intestinal and extraintestinal infection. Gal-lectin based vaccinations have conferred protection in various animal models against E. histolytica infections. Keeping in view the pivotal role of Gal/GalNAc lectin in amoebiasis vaccine development, its regulation, genomic view of the parasite involving gene conversion in lectin gene families, current knowledge about involvement of Gal/GalNAc lectin in adherence, pathogenicity, signalling, encystment, generating host immune response, and in turn protozoa escape strategies, and finally its role as effective vaccine candidate has been described. This review will help researchers to explore pathogenesis mechanism along with genomic studies and will also provide a framework for future amoebiasis vaccine development studies.