Seed phytic acid reduces mineral bioavailability by chelating minerals. Consumption of common bean seeds with the low phytic acid 1 (lpa1) mutation improved iron status in human trials but caused adverse gastrointestinal effects, presumably due to increased stability of lectin phytohemagglutinin L (PHA-L) compared to the wild type (wt). A hard-to-cook (HTC) defect observed in lpa1 seeds intensified this problem. We quantified the HTC phenotype of lpa1 common beans with three genetic backgrounds. The HTC phenotype in the lpa1 black bean line correlated with the redistribution of calcium particularly in the cell walls, providing support for the "phytase-phytate-pectin" theory of the HTC mechanism. Furthermore, the excess of free cations in the lpa1 mutation in combination with different PHA alleles affected the stability of PHA-L lectin.

A series of genetically related lines of common bean (Phaseolus vulgaris L.) integrate a progressive deficiency in major storage proteins, the 7S globulin phaseolin and lectins. SARC1 integrates a lectin-like protein, arcelin-1 from a wild common bean accession. SMARC1N-PN1 is deficient in major lectins, including erythroagglutinating phytohemagglutinin (PHA-E) but not ?-amylase inhibitor, and incorporates also a deficiency in phaseolin. SMARC1-PN1 is intermediate and shares the phaseolin deficiency. Sanilac is the parental background. To understand the genomic basis for variations in protein profiles previously determined by proteomics, the genotypes were submitted to short-fragment genome sequencing using an Illumina HiSeq 2000/2500 platform. Reads were aligned to reference sequences and subjected to de novo assembly. The results of the analyses identified polymorphisms responsible for the lack of specific storage proteins, as well as those associated with large differences in storage protein expression. SMARC1N-PN1 lacks the lectin genes pha-E and lec4-B17, and has the pseudogene pdlec1 in place of the functional pha-L gene. While the ?-phaseolin gene appears absent, an approximately 20-fold decrease in ?-phaseolin accumulation is associated with a single nucleotide polymorphism converting a G-box to an ACGT motif in the proximal promoter. Among residual lectins compensating for storage protein deficiency, mannose lectin FRIL and ?-amylase inhibitor 1 genes are uniquely present in SMARC1N-PN1. An approximately 50-fold increase in ?-amylase inhibitor like protein accumulation is associated with multiple polymorphisms introducing up to eight potential positive cis-regulatory elements in the proximal promoter specific to SMARC1N-PN1. An approximately 7-fold increase in accumulation of 11S globulin legumin is not associated with variation in proximal promoter sequence, suggesting that the identity of individual proteins involved in proteome rebalancing might also be determined at the translational level.

The pathologist Samuel Taylor Darling discovered in 1905 a new disease caused by apreviously not described microrganism that he named Histoplasma capsulatum based on an archaicterm for macrophages (Histo), its resemblance to protozoan parasites (plasma), and the apparentpresence of a surrounding capsule (capsulatum). However, it turned out that it was a fungus and notencapsulated. In the last few decades, fungal infections have become more widespread due to the AIDSepidemic end to the increase in immune compromised state of patients under chemotherapic treatment,extensive use of antibiotics and organ transplants. In parallel with the developments of molecularbiology tools, our knowledge of the mechanism of virulence and host-parasite interactions have alsoincreased significantly. This chapter will highlight the major findings in these areas of investigationfocusing on the biology of the virulence determinants of H.capsulatum. © 2012 Bentham Science Publishers. All rights reserved.

An efficient method for the direct and covalent decoration of granules of nanostructured apatite with a sample monosaccharide is presented: the hydroxyapatite material was directly functionalised with a short azido-containing spacer arm, to which alpha-propargyl glucopyranoside has been chemoselectively ligated by Huisgen-type cycloaddition. The 'glycosylated' hydroxypatite was characterised by its ability to interact with glucose recognising lectins. (C) 2011 Elsevier Ltd. All rights reserved.

Lectins are a class of defence proteins of non-immune origin that bind carbohydrate in a reversible fashion. In some cultivated legume species, lectin protein coding genes were PCR amplified using primers designed on the basis of conserved N- and C-terminal amino acid sequences of the common bean (one-chain) or pea (two-chains) lectins. Amplification products of the expected length were obtained in Lathyrus sativus L., Vicia faba L. var. major, Phaseolus coccineus L., and Vigna unguiculata (L.) Walp. No amplification product or agglutinating activity against blood cells, and/or cross-reaction with specific antibodies were detected in Lupinus albus L. and Cicer arietinum L. Finally, the new isolated nucleotide sequences, together with other legume lectin sequences already present in the EMBL Database, were used for evolutionary analysis. This last indicated the existence of two main clusters; one grouping all the species belonging to the Phaseoleae tribe and the other one grouping Lens culinaris Medik., Pisum sativum L., L. sativus, and V. faba, members of the Vicieae tribe. Results were congruent with the taxonomic classification and suggested that the lectin genes divergence in legume followed species evolution.

The seeds of Phaseolus vulgaris cv. Pinto III are known to lack detectable amounts of phytohemagglutinin (PHA) and to accumulate very reduced levels of PHA mRNA compared with normal cultivars. Using PHA complementary-DNA clones and monospecific antibodies we analyzed cv. Pinto III genomic DNA and cotyledonary proteins synthesized both in vitro and in vivo. We detected genomic DNA sequences that hybridize with complementary-DNA clones for the two different classes of PHA polypeptides (PHA-E and PHA-L), at levels comparable to a normal bean cultivar. This indicates that the cv. Pinto III phenotype is not the result of a large deletion of the PHA structural genes. Messenger RNA isolated from cv. Pinto III developing cotyledons synthesizes in vitro very small amounts of a protein which is recognized by antibodies specific for PHA, and gives, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a single band with molecular weight similar but not identical to that of PHA-L polypeptides. This protein is also synthesized in vivo at a very reduced level, less than 1% compared with PHA in normal cultivars, and has mitogenic activity comparable to that of the PHA-L subunit, while it shows very weak erythroagglutinating activity. The initial steps in the synthesis and processing of this protein are identical to those already identified for PHA polypeptides. The cv. Pinto III protein could be either a PHA-L polypeptide whose synthesis is not affected by the mutation or a PHA-like lectin present normally at low levels in P. vulgaris. © 1985 Springer-Verlag.