Camel and bovine chymosin:the relationship between their structures and cheese-making properties

Bovine and camel chymosin are aspartic peptidases that are used industrially in cheese production. They cleave the Phe105-Met106 bond of the milk protein κ-casein, releasing its predominantly negatively charged C-terminus, which leads to the separation of the milk into curds and whey. Despite having 85% sequence identity, camel chymosin shows a 70% higher milk-clotting activity than bovine chymosin towards bovine milk. The activities, structures, thermal stabilities and glycosylation patterns of bovine and camel chymosin obtained by fermentation in Aspergillus niger have been examined. Different variants of the enzymes were isolated by hydrophobic interaction chromatography and showed variations in their glycosylation, N-terminal sequences and activities. Glycosylation at Asn291 and the loss of the first three residues of camel chymosin significantly decreased its activity. Thermal differential scanning calorimetry revealed a slightly higher thermal stability of camel chymosin compared with bovine chymosin. The crystal structure of a doubly glycosylated variant of camel chymosin was determined at a resolution of 1.6 Å and the crystal structure of unglycosylated bovine chymosin was redetermined at a slightly higher resolution (1.8 Å) than previously determined structures. Camel and bovine chymosin share the same overall fold, except for the antiparallel central β-sheet that connects the N-terminal and C-­terminal domains. In bovine chymosin the N-terminus forms one of the strands which is lacking in camel chymosin. This difference leads to an increase in the flexibility of the relative orientation of the two domains in the camel enzyme. Variations in the amino acids delineating the substrate-binding cleft suggest a greater flexibility in the ability to accommodate the substrate in camel chymosin. Both enzymes possess local positively charged patches on their surface that can play a role in interactions with the overall negatively charged C-terminus of κ-casein. Camel chymosin contains two additional positive patches that favour interaction with the substrate. The improved electrostatic interactions arising from variation in the surface charges and the greater malleability both in domain movements and substrate binding contribute to the better milk-clotting activity of camel chymosin towards bovine milk

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Legume receptors perceive the rhizobial lipochitin oligosaccharide signal molecules by direct binding

Lipochitin oligosaccharides called Nod factors function as primary rhizobial signal molecules triggering legumes to develop new plant organs: root nodules that host the bacteria as nitrogen-fixing bacteroids. Here, we show that the Lotus japonicus Nod factor receptor 5 (NFR5) and Nod factor receptor 1 (NFR1) bind Nod factor directly at high-affinity binding sites. Both receptor proteins were posttranslationally processed when expressed as fusion proteins and extracted from purified membrane fractions of Nicotiana benthamiana or Arabidopsis thaliana. The N-terminal signal peptides were cleaved, and NFR1 protein retained its in vitro kinase activity. Processing of NFR5 protein was characterized by determining the N-glycosylation patterns of the ectodomain. Two different glycan structures with identical composition, Man(3)XylFucGlcNAc(4), were identified by mass spectrometry and located at amino acid positions N68 and N198. Receptor–ligand interaction was measured by using ligands that were labeled or immobilized by application of chemoselective chemistry at the anomeric center. High-affinity ligand binding was demonstrated with both solid-phase and free solution techniques. The K(d) values obtained for Nod factor binding were in the nanomolar range and comparable to the concentration range sufficient for biological activity. Structure-dependent ligand specificity was shown by using chitin oligosaccharides. Taken together, our results suggest that ligand recognition through direct ligand binding is a key step in the receptor-mediated activation mechanism leading to root nodule development in legumes

COpenhagen Neuroplastic TRaining against Contractures in Toddlers (CONTRACT):Protocol of an open-label randomised clinical trial with blinded assessment for prevention of contractures in infants with high risk of cerebral palsy

INTRODUCTION: Contractures are frequent causes of reduced mobility in children with cerebral palsy (CP) already at the age of 2–3 years. Reduced muscle use and muscle growth have been suggested as key factors in the development of contractures, suggesting that effective early prevention may have to involve stimuli that can facilitate muscle growth before the age of 1 year. The present study protocol was developed to assess the effectiveness of an early multicomponent intervention, CONTRACT, involving family-oriented and supervised home-based training, diet and electrical muscle stimulation directed at facilitating muscle growth and thus reduce the risk of contractures in children at high risk of CP compared with standard care. METHODS AND ANALYSIS: A two-group, parallel, open-label randomised clinical trial with blinded assessment (n=50) will be conducted. Infants diagnosed with CP or designated at high risk of CP based on abnormal neuroimaging or absent fidgety movement determined as part of General Movement Assessment, age 9–17 weeks corrected age (CA) will be recruited. A balanced 1:1 randomisation will be made by a computer. The intervention will last for 6 months aiming to support parents in providing daily individualised, goal-directed activities and primarily in lower legs that may stimulate their child to move more and increase muscle growth. Guidance and education of the parents regarding the nutritional benefits of docosahexaenic acid (DHA) and vitamin D for the developing brain and muscle growth will be provided. Infants will receive DHA drops as nutritional supplements and neuromuscular stimulation to facilitate muscle growth. The control group will receive standard care as offered by their local hospital or community. Outcome measures will be taken at 9, 12, 18, 24, 36 and 48 months CA. Primary and secondary outcome measure will be lower leg muscle volume and stiffness of the triceps surae musculotendinous unit together with infant motor profile, respectively. ETHICS AND DISSEMINATION: Full approval from the local ethics committee, Danish Committee System on Health Research Ethics, Region H (H-19041562). Experimental procedures conform with the Declaration of Helsinki. TRIAL REGISTRATION NUMBER: NCT04250454. EXPECTED RECRUITMENT PERIOD: 1 January 2021–1 January 2025

Hur mår unga flyktingar i Norden? Coming of Age in Exile – CAGE

Alla de fyra nordiska länderna har nationella register med uppgifter som kan användas för att beskriva flyktingungdomars situation när det gäller hälsa och sociala livsvillkor. Detta ger unika möjligheter för jämförelser mellan de nordiska länderna för att bättre förstå hur policy och ekonomiska förhållanden i samhället påverkar integrationen av unga invandrare. CAGE har undersökt ojämlikhet i utbildning, arbetsmarknadsdeltagande och hälsa hos unga flyktingar under deras formativa ungdomsår jämfört med infödda, och har också undersökt hur dessa ojämlikheter förhåller sig till nationell invandringspolitik och andra kontextuella faktorer

How are young refugees doing in the Nordic welfare societies? Coming of Age in Exile – CAGE

All the Nordic countries have excellent data on the situation of refugee children and youth. This creates unique opportunities for comparison to better understand the links between the socio-economic context in each country and the integration of young immigrants.  CAGE has investigated inequalities in education, labour market participation and the health of young refugees during their formative years, also looking into how these inequalities relate to national immigration policies and other contextual factors

Hvordan går det med unge flyktninger i Norden? Coming of Age in Exile – CAGE

Alle de fire nordiske landene har gode nasjonale registerdata om unge flyktningers situasjon når det gjelder deres helse og sosiale livsvilkår. Dette gir unike muligheter for sammenligning mellom de nordiske landene for å kunne forstå hvordan landenes politikk og sosioøkonomiske forhold påvirker integrering av unge innvandrere.  CAGE har undersøkt ulikheter i utdanning, arbeidsmarkedsdeltakelse og helse hos unge flyktninger i løpet av deres oppvekst sammenlignet med tilsvarende grupper av barn og unge i majoritetsbefolkningen. Studien har også undersøkt hvordan disse ulikhetene forholder seg til nasjonal innvandringspolitikk og andre kontekstuelle faktorer

Miten pakolaistaustaiset nuoret voivat pohjoismaisissa hyvinvointivaltioissa? Coming of Age in Exile – CAGE

Kaikilla Pohjoismailla on kerättynä erinomaista aineistoa pakolaislasten ja -nuorten tilanteesta. Tämä luo ainutlaatuisia mahdollisuuksia vertailla ja ymmärtää paremmin kunkin maan sosioekonomisen tilanteen ja nuorten maahanmuuttajien kotoutumisen välisiä yhteyksiä.  CAGE-hankkeessa tutkittiin pakolaisnuorten eriarvoisuutta koulutuksessa, työmarkkinoille osallistumisessa ja terveydessä heidän nuoruusvuosiensa aikana. Lisäksi selvitettiin, miten nämä eriarvoisuudet linkittyvät kansalliseen maahanmuuttopolitiikkaan ja sen kontekstiin

Hvernig farnast ungu flóttafólki á Norðurlöndum? Coming of Age in Exile – CAGE

Öll norrænu ríkin safna ítarlegum gögnum um stöðu barna og unglinga í hópi flóttafólks. Gögnin gera það að verkum að hægt er að bera saman stöðuna milli landa og auka skilning á þeim áhrifum sem félags- og efnahagslegar aðstæður hafa á aðlögun ungra innflytjenda. CAGE verkefnið rannsakaði ójöfnuð varðandi menntun, atvinnuþátttöku og heilsufar ungs flóttafólks á uppvaxtarárum þess. Jafnframt varpaði verkefnið ljósi á áhrif innflytjendastefnu landanna og annarra þjóðfélagsþátta á ójöfnuðinn