A5059609322- Physiological and biochemical adaptations
- nanoparticles nucleation surface interactions
- Freezing and Crystallization Processes
- Spaceflight effects on biology
- Reproductive Biology and Fertility
- Insect and Arachnid Ecology and Behavior
- Neurobiology and Insect Physiology Research
- thermodynamics and calorimetric analyses
- Bacteriophages and microbial interactions
- Arctic and Antarctic ice dynamics
- Muscle metabolism and nutrition
- Ocean Acidification Effects and Responses
- Plant Molecular Biology Research
- Polar Research and Ecology
- Material Dynamics and Properties
- Microfluidic and Bio-sensing Technologies
- Protein Structure and Dynamics
- RNA and protein synthesis mechanisms
- Genomics and Phylogenetic Studies
- Molecular Biology Techniques and Applications
- DNA and Nucleic Acid Chemistry
- Tardigrade Biology and Ecology
- Solidification and crystal growth phenomena
- Icing and De-icing Technologies
- Marine Bivalve and Aquaculture Studies
Hebrew University of Jerusalem
2016-2025
Smith Institute
2014-2023
Institute for Information Transmission Problems
2019
Stanford University
2008-2019
Ohio University
2008-2017
Università di Camerino
2016
South Ukrainian National Pedagogical University named after K. D. Ushynsky
2015
Food and Nutrition Service
2014
Weizmann Institute of Science
1999-2009
Howard Hughes Medical Institute
2008
The full promise of human genomics will be realized only when the genomes thousands individuals can sequenced for comparative analysis. A reference sequence enables use short read length. We report an amplification-free method determining nucleotide more than 280,000 individual DNA molecules simultaneously. polymerase adds labeled nucleotides to surface-immobilized primer-template duplexes in stepwise fashion, and asynchronous growth was monitored by fluorescence imaging. Read lengths >25...
The completion of the human genome draft has taken several years and is only beginning a period in which large amounts DNA RNA sequence information will be required from many individuals species. Conventional sequencing technology limitations cost, speed, sensitivity, with result that demand for far outstrips current capacity. There have been proposals to address these issues by developing ability single molecules, but none experimentally demonstrated. Here we report use polymerase obtain...
Antifreeze proteins (AFPs) are a subset of ice-binding that control ice crystal growth. They have potential for the cryopreservation cells, tissues, and organs, as well production storage food protection crops from frost. However, detailed mechanism action AFPs is still unclear. Specifically, there controversy regarding reversibility binding to surfaces. The experimentally observed dependence activity on their concentration in solution appears indicate reversible. Here, by series experiments...
It has been argued that for antifreeze proteins (AFPs) to stop ice crystal growth, they must irreversibly bind the surface. Surface-adsorbed AFPs should also prevent from melting, but date this demonstrated only in a qualitative manner. Here we present first quantitative measurements of superheating AFP solutions. Superheated crystals were stable hours above their equilibrium melting point, and maximum obtained was 0.44 °C. When commenced superheated regime, rapid point on surface observed....
Bacterial adhesins are modular cell-surface proteins that mediate adherence to other cells, surfaces, and ligands. The Antarctic bacterium Marinomonas primoryensis uses a 1.5-MDa adhesin comprising over 130 domains position it on ice at the top of water column for better access oxygen nutrients. We have reconstructed this 0.6-μm-long using "dissect build" structural biology approach established complementary roles its five distinct regions. Domains in region I (RI) tether type secretion...
Several types of natural molecules interact specifically with ice crystals. Small antifreeze proteins (AFPs) adsorb to particular facets crystals, thus inhibiting their growth, whereas larger ice-nucleating (INPs) can trigger the formation new crystals at temperatures much higher than homogeneous nucleation temperature pure water. It has been proposed that both similarly and that, in principle, they may be able exhibit functions. Here we investigated two naturally occurring proteins, one...
Antifreeze proteins (AFPs) evolved in many organisms, allowing them to survive cold climates by controlling ice crystal growth. The specific interactions of AFPs with determine their potential applications agriculture, food preservation and medicine. control the shapes crystals a manner characteristic particular AFP type. Moderately active cause formation elongated bipyramidal crystals, often seemingly defined facets, while hyperactive produce more varied shapes. These different morphologies...
Ice-binding proteins that aid the survival of freeze-avoiding, cold-adapted organisms by inhibiting growth endogenous ice crystals are called antifreeze (AFPs). The binding AFPs to causes a separation between melting point and freezing crystal (thermal hysteresis, TH). TH produced hyperactive is an order magnitude higher than typical fish AFP. basis for this difference in activity remains unclear. Here, we have compared time dependence both moderately active using custom-made nanolitre...
Antifreeze proteins (AFPs) are a widespread class of that bind to ice and facilitate the survival organisms under freezing conditions. AFPs have enormous potential in applications require control over growth. However, nature binding interaction between remains subject debate. Using microfluidics system developed in-house we previously showed hyperactive AFP from Tenebrio molitor beetle, TmAFP, bound an crystal surface after exchanging solution surrounding AFP-free solution. Furthermore,...
Cold environments are populated by organisms able to contravene deleterious effects of low temperature diverse adaptive strategies, including the production ice binding proteins (IBPs) that inhibit growth crystals inside and outside cells. We describe properties such a protein (EfcIBP) identified in metagenome an Antarctic biological consortium composed ciliate Euplotes focardii psychrophilic non-cultured bacteria. Recombinant EfcIBP can resist freezing without any conformational damage is...
We studied the interaction between integration host factor (IHF), a major nucleoid-associated protein in bacteria, and single DNA molecules. Force–extension measurements of λ an analysis Brownian motion small beads tethered to surface by short molecules, equilibrium with IHF solution, indicate that: ( i ) DNA–IHF complex retains random, although more compact, coiled configuration for zero or values tension, ii induces compaction binding multiple sites low specificity, iii increasing tension...
By binding to the surface of ice crystals, type III antifreeze protein (AFP) can depress freezing point fish blood below that seawater. This 7-kDa globular is encoded by a multigene family produces two major isoforms, SP and QAE, which are 55% identical. Disruptive mutations on ice-binding site AFP lower activity but also change crystal morphology. attaching green fluorescent different mutants isoforms examining these fusion proteins single-crystal hemispheres, we show has compound site....
Ice-binding proteins (IBPs), including antifreeze proteins, ice structuring thermal hysteresis and recrystallization inhibition are found in cold-adapted organisms protect them from freeze injuries by interacting with crystals. IBPs a variety of organism, fish(1), plants(2, 3), arthropods(4, 5), fungi(6), bacteria(7). adsorb to the surfaces crystals prevent water molecules joining lattice at IBP adsorption location. Ice that grows on crystal surface between adsorbed develops high curvature...
Ice-binding proteins (IBPs) are typically small, soluble produced by cold-adapted organisms to help them avoid ice damage either resisting or tolerating freezing. By contrast, the IBP of Antarctic bacterium Marinomonas primoryensis is an extremely long, 1.5 MDa protein consisting five different regions. The fourth region, a 34 kDa domain, only part that confers binding. Bioinformatic studies suggest this serves as adhesin attaches bacteria keep it near top water column, where oxygen and...
Successfully cryopreserving cells adhered to a substrate would facilitate the growth of vital confluent cell culture after thawing while dramatically shortening post-thaw culturing time. Herein we propose controlled slow cooling method combining initial directional freezing followed by gradual down -80°C for robust preservation monolayers adherent substrate. Using computer cryostages examined effect rates and dimethylsulfoxide (DMSO) concentration on survival established an optimal...
Aerogel objects inspired by plant cell wall components and structures were fabricated using extrusion-based 3D printing at cryogenic temperatures. The process combines with the alignment of rod-shaped nanoparticles through freeze-casting aqueous inks. We have named this method direct cryo writing (DCW) as it encompasses in a single processing step traditional directional freeze casting spatial fidelity printing. DCW is demonstrated inks that are composed an mixture cellulose nanocrystals...
Abstract Bacterial ice nucleation proteins (INPs) can cause frost damage to plants by nucleating formation at high sub-zero temperatures. Modeling of Pseudomonas borealis INP AlphaFold suggests that the central domain 65 tandem sixteen-residue repeats forms a beta-solenoid with arrays outward-pointing threonines and tyrosines, which may organize water molecules into an ice-like pattern. Here we report mutating some these residues in segment P. INP, expressed Escherichia coli , decreases...
The formation of ice and frost on surfaces poses significant challenges to aviation, crop protection, organ preservation, other fields. This paper presents the sustainable antifreeze coating by self-assembly short peptides. peptide design is inspired combines different elements from distinct natural proteins: (i) a sequence amino acids an protein (ii) 3,4-dihydroxyphenylalanine (DOPA) lysine mussel adhesion proteins that anchor surface. peptide, termed AFPep1, incorporates repetitive...
The snow flea (Hypogastrum harveyi) is protected from freezing at sub-zero temperatures by a glycine-rich antifreeze protein (AFP) that binds to seed ice crystals and prevents them growing larger. This AFP hyperactive comprises two isoforms [Graham, L. A., Davies, P. (2005) Science 310, 461]. larger isoform (15.7 kDa) exhibits several-fold higher activity than the smaller (6.5 kDa), although it considerably less abundant. To establish molecular basis for this difference in activity, we...
The control over ice crystal growth, melting, and shaping is important in a variety of fields, including cell food preservation templating for the production composite materials. Control growth remains challenge industry, demand new cryoprotectants high. Naturally occurring cryoprotectants, such as antifreeze proteins (AFPs), present one solution modulating growth; however, AFPs expensive inefficient. These obstacles can be overcome by identifying synthetic substitutes with similar AFP...