Anti-Fungal Hevein-like Peptides Biosynthesized from Quinoa Cleavable Hololectins

Chitin-binding hevein-like peptides (CB-HLPs) belong to a family of cysteine-rich peptides that play important roles in plant stress and defense mechanisms. CB-HLPs are ribosomally synthesized peptides that are known to be bioprocessed from the following two types of three-domain CB-HLP precursor architectures: cargo-carrying and non-cargo-carrying. Here, we report the identification and characterization of chenotides biosynthesized from the third type of precursors, which are cleavable hololectins of the quinoa (Chenopodium quinoa) family. Chenotides are 6-Cys-CB-HLPs of 29–31 amino acids, which have a third type of precursor architecture that encompasses a canonical chitin-binding domain that is involved in chitin binding and anti-fungal activities. Microbroth dilution assays and microscopic analyses showed that chenotides are effective against phyto-pathogenic fungi in the micromolar range. Structure determination revealed that chenotides are cystine knotted and highly compact, which could confer resistance against heat and proteolytic degradation. Importantly, chenotides are connected by a novel 18-residue Gly/Ala-rich linker that is a target for bioprocessing by cathepsin-like endopeptidases. Taken together, our findings reveal that chenotides are a new family of CB-HLPs from quinoa that are synthesized as a single multi-modular unit and bioprocessed to yield individual mature CB-HLPs. Importantly, such precursors constitute a new family of cleavable hololectins. This unusual feature could increase the biosynthetic efficiency of anti-fungal CB-HLPs, to provide an evolutionary advantage for plant survival and reproduction.

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Parasite defense mechanisms in bees: behavior, immunity, antimicrobials, and symbionts

Emerging Topics in Life Sciences ◽

10.1042/etls20190069 ◽

2019 ◽

Vol 4 (1) ◽

pp. 59-76 ◽

Cited By ~ 2

Author(s):

Alison E. Fowler ◽

Rebecca E. Irwin ◽

Lynn S. Adler

Keyword(s):

Defense Mechanisms ◽

Poor Quality ◽

Future Research ◽

Immune Priming ◽

Social Bees ◽

Bee Health ◽

Landscape Scales ◽

And Function ◽

Solitary Species

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.

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Discovery and characterization of a new family of primitive moths (Aenigmatineidae) from Kangaroo Island, South Australia

10.1603/ice.2016.95258 ◽

2016 ◽

Author(s):

Douglas Hilton

Keyword(s):

South Australia ◽

New Family

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An Intrinsic Characterization of Five Points in a CAT(0) Space

Analysis and Geometry in Metric Spaces ◽

10.1515/agms-2020-0111 ◽

2020 ◽

Vol 8 (1) ◽

pp. 114-165

Author(s):

Tetsu Toyoda

Keyword(s):

Metric Space ◽

Isometric Embedding ◽

Metric Spaces ◽

Necessary Conditions ◽

New Approach ◽

Intrinsic Characterization ◽

New Family

AbstractGromov (2001) and Sturm (2003) proved that any four points in a CAT(0) space satisfy a certain family of inequalities. We call those inequalities the ⊠-inequalities, following the notation used by Gromov. In this paper, we prove that a metric space X containing at most five points admits an isometric embedding into a CAT(0) space if and only if any four points in X satisfy the ⊠-inequalities. To prove this, we introduce a new family of necessary conditions for a metric space to admit an isometric embedding into a CAT(0) space by modifying and generalizing Gromov’s cycle conditions. Furthermore, we prove that if a metric space satisfies all those necessary conditions, then it admits an isometric embedding into a CAT(0) space. This work presents a new approach to characterizing those metric spaces that admit an isometric embedding into a CAT(0) space.

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Semi-Crystalline Hydrophobic Polyamidoamines: A New Family of Technological Materials?

Polymers ◽

10.3390/polym13071018 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1018

Author(s):

Massimo Marcioni ◽

Jenny Alongi ◽

Elisabetta Ranucci ◽

Mario Malinconico ◽

Paola Laurienzo ◽

...

Keyword(s):

Maximum Stress ◽

Water Resistance ◽

Prolonged Exposure ◽

Water Soluble ◽

Synthesis And Characterization ◽

Molecular Weights ◽

New Family ◽

Methylene Groups ◽

Methane Flame

The hitherto known polyamidoamines (PAAs) are not suitable as structural materials because they are usually water-soluble or swellable in water. This paper deals with the synthesis and characterization of semi-crystalline hydrophobic PAAs (H-PAAs) by combining different bis-sec-amines with bis-acrylamides obtained from C6–C12 bis-prim-amines. H-PAAs were initially obtained in a solution of benzyl alcohol, a solvent suitable for both monomers and polymers. Their number average molecular weights, M¯n, which were determined with 1H-NMR by evaluating the percentage of their terminal units, varied from 6000 to >10,000. The solubility, thermal properties, ignitability and water resistance of H-PAAs were determined. They were soluble in organic solvents, semi-crystalline and thermally stable. The most promising ones were also prepared using a bulk process, which has never been previously reported for PAA synthesis. In the form of films, these H-PAAs were apparently unaffected by water. The films underwent tensile and wettability tests. They showed similar Young moduli (260–263 MPa), whereas the maximum stress and the stress at break depended on the number of methylene groups of the starting bis-acrylamides. Their wettability was somewhat higher than that of common Nylons. Interestingly, none of the H-PAAs considered, either as films or powders, ignited after prolonged exposure to a methane flame.

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Microfluidic Tools for Enhanced Characterization of Therapeutic Stem Cells and Prediction of Their Potential Antimicrobial Secretome

Antibiotics ◽

10.3390/antibiotics10070750 ◽

2021 ◽

Vol 10 (7) ◽

pp. 750

Author(s):

Pasquale Marrazzo ◽

Valeria Pizzuti ◽

Silvia Zia ◽

Azzurra Sargenti ◽

Daniele Gazzola ◽

...

Keyword(s):

Stem Cells ◽

Defense Mechanisms ◽

Live Cells ◽

Label Free ◽

Bacterial Diseases ◽

Prospective Application ◽

Therapy Strategies ◽

Stromal Stem Cells ◽

Different Sources

Antibiotic resistance is creating enormous attention on the development of new antibiotic-free therapy strategies for bacterial diseases. Mesenchymal stromal stem cells (MSCs) are the most promising candidates in current clinical trials and included in several cell-therapy protocols. Together with the well-known immunomodulatory and regenerative potential of the MSC secretome, these cells have shown direct and indirect anti-bacterial effects. However, the low reproducibility and standardization of MSCs from different sources are the current limitations prior to the purification of cell-free secreted antimicrobial peptides and exosomes. In order to improve MSC characterization, novel label-free functional tests, evaluating the biophysical properties of the cells, will be advantageous for their cell profiling, population sorting, and quality control. We discuss the potential of emerging microfluidic technologies providing new insights into density, shape, and size of live cells, starting from heterogeneous or 3D cultured samples. The prospective application of these technologies to studying MSC populations may contribute to developing new biopharmaceutical strategies with a view to naturally overcoming bacterial defense mechanisms.

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