Higher Protein Score Research Articles

Dietary protein score and carbohydrate quality index with the risk of chronic kidney disease: Findings from a prospective cohort study.

This study aimed to examine the associations between dietary protein score and carbohydrate quality index (CQI) and the risk of chronic kidney disease (CKD) in Iranian adults. This population-based cohort study was performed within the Tehran Lipid and Glucose Study framework on 6,044 subjects aged ≥18 years old, who were followed up for a mean of 7.7 years. Dietary protein score and CQI were determined using a food frequency questionnaire. CKD was defined as an estimated glomerular filtration rate <60 ml/min/1.73 m2. A multivariate Cox proportional hazard regression model was used to estimate the risk of CKD across tertiles of protein score and CQI. The mean (standard deviation) of age and body mass index of participants were 37.9 (12.8) years and 26.8 (4.7) kg/m2, respectively. During the 7.7 ± 2.7 years of follow-up, 1,216 cases (20.1%) of CKD were ascertained. In the final adjusted model, individuals in the highest tertile of protein score had decreased risk of CKD (HR: 0.85, 95% CI: 0.74-0.98, P trend = 0.033). Also, there is a significant association between total carbohydrate score (HR: 0.85, 95% CI: 0.73-0.99, P trend = 0.016), the ratio of whole grain/total grains (HR: 0.81, 95% CI: 0.70-0.94, P trend = 0.004), and glycemic index (HR: 1.30, 95% CI: 1.12-1.51, P trend < 0.001) and risk of CKD. However, no significant association was found between total protein intakes, plant-to-animal ratio, and solid carbohydrate/total carbohydrate with the risk of CKD. Our results revealed a diet with a high protein score and high quality of carbohydrates, characterized by higher intakes of plant proteins, low glycaemic index (GI) carbohydrates, whole grain, fibers, and lower intakes of animal proteins, can be related to reduced CKD risk.

Identification of Salmonella Typhimurium Peptidyl-prolyl cis-trans Isomerase B (PPIase B) and Assessment of their Role in the Protein Folding.

Peptidyl-prolyl cis-trans isomerase (PPIases) enzyme plays a vital role in protein folding. It catalyses the cis-trans isomerisation of peptide bonds, an essential step for newly synthesized protein to acquire its correct functional conformation in both prokaryotes and eukaryotes. The present study showed the biochemical and molecular characterisation of cyclophilins (PpiB), a type of peptidyl-prolyl isomerases proteins from the pathogenic bacteria Salmonella Typhimurium. Salmonella Typhimurium is one of the leading serovars responsible for human and animal salmonellosis globally, with the majority of human cases originating through the food chain. Here successful expression and purification of PpiB protein have been demonstrated and LC-MS based analyses showed high protein score and similarity with other PPi protein. Further the enzymatic activity of the purified recombinant PpiB was determined using Succinyl-Ala-Phe-Pro- Phe-p nitroanilide as substrate and enzyme-catalysed reaction. Km and Vmax were calculated and found to be Vm = 1.023 ± .06400 min/μg, Km = 0.6219 ± 0.1701 μM, respectively. We have reported for the first time the presence of Salmonella PPIase-B (PpiB) protein isoforms in salmonella genome having PPi activity. Taken together, our data clearly showed that Salmonella Cyclophilin B (PpiB) protein is active and involved in diverse biological processes and highly similar to the different domain of Cyclophilin proteins.

The effect of finishing diet supplemented with methionine/lysine and methionine/α-tocopherol on performance, carcass traits and meat quality of Hanwoo steers.

ObjectiveThis study aimed to compare the effects of diets with and without supplements of methionine/lysine (met/lys) and methionine/α-tocopherol (met/α-tocopherol) on the performance, carcass traits and meat quality of Hanwoo steers.MethodsA total of 21 Hanwoo steers were divided into three different groups. Each group consisted of 7 animals that received different dietary treatments for 120 days as follows: a control (C) diet composed of a basal diet with 74% total digestible nutrient and 12% crude protein; treatment 1 (T1) composed of a basal diet enriched with methionine 69%+lysine 31%; and treatment (T2) composed of a basal diet enriched with methionine 84.65%+α-tocopherol 15.35%. Daily supplementation was given using the top-dressing method (20 g/animal).ResultsThe met/lys groups yielded a longissimus lumborum with increased water holding capacity (p<0.01) and lower shear force value (p<0.05). Dietary met/lys did not have an adverse effect on the animal performance and carcass traits. Instead, these supplements contributed significantly to the higher protein content compared to the control diet (p<0.05). Myristic acid (C14:0) was the only fatty acid affected by the supplementation. While the met/α-tocopherol group led to significantly higher protein and oxymyoglobin contents during storage (p<0.05). It also contributed significantly to the lower shear force value and 2-thiobarbituric acid reactive substances score during storage (p<0.05) compared to the control and treatment 1 since the initial storage day. The met/α-tocopherol diet also yielded meat with a redder color (p<0.05) after 3 days of storage. However, it did not significantly contribute to the fatty acid profiles of Hanwoo steers.ConclusionMet/lys supplementation resulted in higher protein scores, water holding capacity and lower shear force scores. While met/α-tocopherol supplementation contributes to the production of redder meat, reduces lipid oxidation, production of more tender meat and increases the content of protein and oxymyoglobin percentage.

Prefractionation methods for individual adult fruit fly hemolymph proteomic analysis.

The analysis of blood provides in depth chemical information of physiological states of organisms. Hemolymph (blood) is the fluid in the open circulatory system of Drosophila melanogaster that is the medium for molecules regulating a wide variety of physiological activities and signaling between tissues. Adult Drosophila is typically less than 3mm in length and, as a consequence, the available volume of hemolymph is usually less than 50 nL from individual flies. Proteomic analysis of volume-limited hemolymph is a great challenge for both sample handling and subsequent mass spectrometry characterization of this chemically diverse biological fluid with a wide dynamic range of proteins in concentrations. Less abundant proteins, in particular, could be easily lost during sample preparation or missed by current mass spectrometry methods. This article describes simple and customized RPLC column and IEX columns to prefractionate volume-limited hemolymph without excessive dilution. Step-gradient elution methods were developed and optimized to enhance the identification of novel proteins from an individual fruit fly hemolymph sample. Fractions from each step gradient was analyzed by an Agilent nano-RPLC chip column and then characterized by high mass resolution and high mass accuracy orbitrap mass spectrometry. As a result, both RPLC (11 proteins) and IEX fractionation approaches (9 proteins) identified more proteins than an unfractionated control approach with higher protein scores, emPAI values and coverage. Furthermore, a significant number of novel proteins were revealed by both RPLC and IEX fractionation methods, which were missed by unfractionated controls. The demonstration of this method establishes a means to deepen proteomic analysis to this commonly used, important biological model system.

Exploring extra-cellular proteins in methicillin susceptible and methicillin resistant Staphylococcus aureus by liquid chromatography–tandem mass spectrometry

Staphylococcus aureus (S. aureus) strains cause several diseases in humans from minor skin infections to severe lethal infections. To explore the virulence determinants of this important microorganism, two clinical isolates of methicillin susceptible S. aureus (MSSA) and methicillin resistant S. aureus (MRSA) were subjected to proteomic analysis of their extracellular products using liquid chromatography-tandem mass spectrometry. The numbers of proteins identified in MSSA and MRSA extracellular products were 168 and 261; respectively, from them 117 were shared, while 144 proteins were unique to MRSA. The shared proteins, having a higher protein score with increased number of peptide matches in MRSA over MSSA, reflect the relatively active secretory state of MRSA rather than biased analytical variances. Characteristic determinants for MRSA were identified; mostly found to play a role in the virulence. We conclude that MRSA produces distinct proteins considered as its virulence determinants and we found that the shared extracellular products are more abundant in MRSA than MSSA that supporting the high invasiveness of MRSA over MSSA in pathogenesis.

Low-carbohydrate, high-protein score and mortality in a northern Swedish population-based cohort

Long-term effects of carbohydrate-restricted diets are unclear. We examined a low-carbohydrate, high-protein (LCHP) score in relation to mortality. This is a population-based cohort study on adults in the northern Swedish county of Västerbotten. In 37,639 men (1460 deaths) and 39,680 women (923 deaths) from the population-based Västerbotten Intervention Program, deciles of energy-adjusted carbohydrate (descending) and protein (ascending) intake were added to create an LCHP score (2-20 points). Sex-specific hazard ratios (HR) were calculated by Cox regression. Median intakes of carbohydrates, protein and fat in subjects with LCHP scores 2-20 ranged from 61.0% to 38.6%, 11.3% to 19.2% and 26.6% to 41.5% of total energy intake, respectively. High LCHP score (14-20 points) did not predict all-cause mortality compared with low LCHP score (2-8 points), after accounting for saturated fat intake and established risk factors (men: HR for high vs low 1.03 (95% confidence interval (CI) 0.88-1.20), P for continuous = 0.721; women: HR for high vs low 1.10 (95% CI 0.91-1.32), P for continuous = 0.229). For cancer and cardiovascular disease, no clear associations were found. Carbohydrate intake was inversely associated with all-cause mortality, though only statistically significant in women (multivariate HR per decile increase 0.95 (95% CI 0.91-0.99), P = 0.010). Our results do not support a clear, general association between LCHP score and mortality. Studies encompassing a wider range of macronutrient consumption may be necessary to detect such an association.

3510 POSTER Low-carbohydrate, High-protein Score and Cancer Incidence and Mortality in a Northern Swedish Population

Low-carbohydrate, high-protein score and cancer incidence and mortality in a northern swedish population

Yield and Properties of Cottonseed-Cheese whey Protein Coprecipitate Prepared Using Sodium Hexametaphosphate

The best yield conditions for the preparation of cottonseed-cheese whey protein coprecipitate using sodium hexametaphosphate were determined. The coprecipitate was then prepared under these conditions and evaluated for nitrogen yield, acidulant requirement, and properties in comparison with separately precipitated cottonseed and cheese whey proteins. The coprecipitation resulted in an acidulant saving but slightly less nitrogen yield than the separate precipitation of cottonseed and cheese whey proteins. The low nitrogen yield maybe improved by reducing the concentration of cations in cheese whey which competes with protein for phosphate ions. The coprecipitate had a higher protein score and protein efficiency ratio than the cottonseed isolate and the cottonseed isolate-cheese whey mixture, suggesting the nutritional advantage of the coprecipitation process over separate precipitation of cottonseed and cheese whey proteins. Although the coprecipitate had better functional properties than the cotton seed isolate, it did not differ very much from the cottonseed-cheese whey isolate mixture.

COPRECIPITATION OF CHEESE WHEY WITH SOYBEAN AND COTTONSEED PROTEINS USING ACID AND HEAT TREATMENT

ABSTRACTSoybean‐ and cottonseed‐whey protein coprecipitate isolates (SIW and CIW) and coprecipitate concentrates (SCW and CCW) were all prepared using heat treatment (95°C, 15 min) at acidic pH (4.6). Soybean and cottonseed protein isolates (SI and CI) and concentrates (SC and CC) and whey protein concentrate (WC) were also prepared under similar conditions for comparison with the coprecipitates. In general, the coprecipitation resulted in acidulant savings (7–9% for SIW and CIW, 51–68% for SCW and CCW), higher nitrogen yields (24–29% for SIW and SCW, 10–17% for CIW and CCW), higher protein scores, lighter color, slightly higher solubility, lower water and fat absorption and emulsifying capacities compared with separate precipitation of the oil‐seed proteins. The whipping properties decreased in the coprecipitate isolate but increased in the coprecipitate concentrate of soybean and cottonseed. Compared with a commercial soy isolate, all coprecipitates had lower solubility, emulsifying and whipping capacities but equivalent water and fat absorption capacities.

Coprecipitation of Rapeseed and Cheese Whey Proteins Using Acid and Heat Treatment

Rapeseed protein isolate (RI) and concentrate (RC) prepared with and without added cottage cheese whey (W) were compared. The products with W were called rapeseed isolate-whey coprecipitate (RIW) and rapeseed concentrate-whey coprecipitate (RCW), respectively. RIW had higher protein score and biological value, lighter color, better emulsifying, water and fat absorption capacities but lower whipping properties than RI. RCW had almost similar protein score and biological value, lighter color, lower water and fat absorption capacities but higher emulsifying and whipping properties than RC. In general, rapeseed-whey protein coprecipitation resulted in lower acidulant requirement and higher nitrogen yield than the separate precipitation of the two proteins. The amino acid pattern and some functional properties of the coprecipitates deviated from mixtures of separately precipitated rapeseed and W proteins which is suggestive of a complex interaction between the two proteins during the coprecipitation process. Compared with a soy protein isolate, the coprecipitates had poorer functionality which could be attributed to the protein denaturation which occurred during the heat treatment (95°C, 15min) involved in their preparation. Glucosinolates were not detectable in the rapeseed products.