scholarly journals The conformational stability of pro-apoptotic BAX is dictated by discrete residues of the protein core

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Noah B. Bloch ◽  
Thomas E. Wales ◽  
Michelle S. Prew ◽  
Hannah R. Levy ◽  
John R. Engen ◽  
...  
Keyword(s):  
Conformational Stability ◽  
Control Point ◽  
Structural Features ◽  
Stress Signaling ◽  
Life And Death ◽  
Critical Control Point ◽  
Cellular Life ◽  
Oligomeric Protein ◽  
Response To Stress ◽  
Conformational Regulation

AbstractBAX is a pro-apoptotic member of the BCL-2 family, which regulates the balance between cellular life and death. During homeostasis, BAX predominantly resides in the cytosol as a latent monomer but, in response to stress, transforms into an oligomeric protein that permeabilizes the mitochondria, leading to apoptosis. Because renegade BAX activation poses a grave risk to the cell, the architecture of BAX must ensure monomeric stability yet enable conformational change upon stress signaling. The specific structural features that afford both stability and dynamic flexibility remain ill-defined and represent a critical control point of BAX regulation. We identify a nexus of interactions involving four residues of the BAX core α5 helix that are individually essential to maintaining the structure and latency of monomeric BAX and are collectively required for dimeric assembly. The dual yet distinct roles of these residues reveals the intricacy of BAX conformational regulation and opportunities for therapeutic modulation.

Insights into the Structural Features, Conformational Stability and Functional Activity of the Olneya tesota PF2 Lectin

2020 ◽  
Vol 27 ◽  
Author(s):  
Edgar Acedo-Espinoza ◽  
Irlanda Lagarda-Diaz ◽  
Rosina Cabrera ◽  
Ana M. Guzman-Partida ◽  
Amir Maldonado-Arce ◽  
...  
Keyword(s):  
Tertiary Structure ◽  
Proteolytic Enzymes ◽  
Conformational Stability ◽  
Structural Features ◽  
Beta Sheets ◽  
Hemagglutinating Activity ◽  
Effect Of Temperature ◽  
Hydrodynamic Diameter ◽  
Bioinformatic Tools ◽  
Structural Levels

Background: The O. tesota lectin PF2 is a tetrameric protein with subunits of 33 kDa that recognizes only complex carbohydrates, resistant to proteolytic enzymes and has insecticidal activity against Phaseolus beans pest. Objective: To explore PF2 lectin features at different protein structural levels and to evaluate the effect of temperature and pH on its functionality and conformational stability. Methods: PF2 lectin was purified by affinity chromatography. Its primary structure was resolved by mass spectrometry and analyzed by bioinformatic tools, including its tertiary structure homology modeling. The effect of temperature and pH on its conformational traits and stability was addressed by dynamic light scattering, circular dichroism, and intrinsic fluorescence. The hemagglutinating activity was evaluated using a suspension of peripheral blood erythrocytes. Results: The proposed PF2 folding comprises a high content of beta sheets. At pH 7 and 25 °C, the hydrodynamic diameter (Dh) was found to be 12.3 nm which corresponds to the oligomeric native state of PF2 lectin. Dh increased under the other evaluated pH and temperature conditions, suggesting protein aggregation. At basic pH, PF2 exhibited low conformational stability. The native PF2 (pH 7) retained its full hemagglutinating activity up to 45 °C and exhibited one transition state with a melting temperature of 76.8 °C. Conclusion: PF2 showed distinctive characteristics found in legume lectins. The pH influences the functionality and conformational stability of the protein. PF2 lectin displayed a relatively narrow thermostability to the loss of secondary structure and hemagglutinating activity.

scholarly journals Seaweed aquaculture: a preliminary assessment of biosecurity measures for controlling the ice-ice syndrome and pest outbreaks of a Kappaphycus farm

2021 ◽  
Author(s):  
Cicilia S. B. Kambey ◽  
Iona Campbell ◽  
Elizabeth J. Cottier-Cook ◽  
Adibi R. M. Nor ◽  
Azhar Kassim ◽  
...  
Keyword(s):  
Hazard Analysis ◽  
Kappaphycus Alvarezii ◽  
Control Point ◽  
Control Measures ◽  
Seaweed Aquaculture ◽  
Critical Control Point ◽  
Management Measures ◽  
Long Line ◽  
Pest Outbreaks ◽  
The Impact

AbstractThe application of biosecurity in seaweed aquaculture plays an important role in reducing the impact of disease and pest outbreaks. The continuous occurrence of seaweed pests including the macroalgal epiphytes, epi-endophytic filamentous algae and biofilms on Kappaphycus farms may also potentially induce further incidences of the ice-ice syndrome. In this study, on-farm biosecurity management measures were tested on the commercially grown seaweeds Kappaphycus malesianus and Kappaphycus alvarezii during peak ice-ice season at Gallam-Gallam Village, Sabah, Malaysia. The investigation was focused on preventative control measures including the early detection of the ice-ice syndrome and pests through propagule health checks, regular cleaning of the crop thallus and associated long-line ropes and monitoring of the environment. Farm procedures and practices were also assessed in terms of their biosecurity ‘risk’ using the hazard analysis and critical control point (HCCAP) approach. Observations were replicated in two different farm management systems; one system adopted routine biosecurity measures and the other had no biosecurity measures. The results showed that the ice-ice syndrome and pest outbreak was significantly decreased by 60–75% for K. malesianus and 29–71% for K. alvarezii at the farm which adopted the routine biosecurity measures compared with the no biosecurity treatment. The biosecurity measures also significantly improved growth rate and seaweed quality. The infection levels of the epi-endophyte Melanothamnus sp. contributed to the ice-ice syndrome in K. malesianus, whilst the epiphyte coverage was correlated to the ice-ice incidence in K. alvarezii. This study provides the first evidence of biosecurity management measures significantly decreasing the incidence of the ice-ice syndrome and pests on a commercial seaweed farm.

scholarly journals Food Allergen Detection Methods: A Coordinated Approach

2004 ◽  
Vol 87 (6) ◽  
pp. 1383-1390 ◽  
Author(s):  
Philip R Goodwin
Keyword(s):  
Hazard Analysis ◽  
Adult Population ◽  
Control Point ◽  
Cost Effective ◽  
Test Methods ◽  
Detection Methods ◽  
Critical Control Point ◽  
Life Threatening ◽  
Monitoring And Surveillance ◽  
Analytical Approaches

Abstract The levels (1–2%) and increasing severity of allergic responses to food in the adult population are well documented, as is the phenomenon of even higher (3–8%) and apparently increasing incidence in children, albeit that susceptibility decreases with age. Problematic foods include peanut, milk, eggs, tree nuts, and sesame, but the list is growing as awareness continues to rise. The amounts of such foods that can cause allergic reactions is difficult to gauge; however, the general consensus is that ingestion of low parts per million is sufficient to cause severe reactions in badly affected individuals. Symptoms can rapidly—within minutes—progress from minor discomfort to severe, even life-threatening anaphylactic shock in those worst affected. Given the combination of high incidence of atopy, potential severity of response, and apparently widespread instances of “hidden” allergens in the food supply, it is not surprising that this issue is increasingly subject to legislative and regulatory scrutiny. In order to assist in the control of allergen levels in foods to acceptable levels, analysts require a combination of test methods, each designed to produce accurate, timely, and cost-effective analytical information. Such information contributes significantly to Hazard Analysis Critical Control Point programs to determine food manufacturers’ risk and improves the accuracy of monitoring and surveillance by food industry, commercial, and enforcement laboratories. Analysis thereby facilitates improvements in compliance with labeling laws with concomitant reductions in risks to atopic consumers. This article describes a combination of analytical approaches to fulfill the various needs of these 3 analytical communities.

Product quality of kaledo, a local food of Palu City Indonesia

Food Research ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 273-278
Author(s):  
Y.I. Jayadi ◽  
A. Astari ◽  
R. Ekasari ◽  
U. Aiman ◽  
N.U. Dewi
Keyword(s):  
Hazard Analysis ◽  
Control Point ◽  
Good Manufacturing Practice ◽  
Cross Sectional Study ◽  
Chemical Contamination ◽  
Self Assessment ◽  
Cross Sectional ◽  
Critical Control Point ◽  
Cooking Process ◽  
Physical And Chemical

Food safety is an important issue in the incidence of foodborne diseases in society. Kaledo is one of the “must-try” traditional foods of Palu City, Indonesia. The main ingredients used for making this dish are beef and cow’s trotters, which are highly susceptible to microbiological, physical, and chemical contamination. This cross-sectional study aimed to analyze the Good Manufacturing Practice (GMP) and Hazard Analysis Critical Control Point (HACCP) in one of the culinary businesses in Palu City. The GMP assessment was carried out using the self-assessment questionnaire developed by Food Supplements Europe. The results of this study indicated that Kaledo X Food Stall still had not implemented GMP. However, HACCP analysis showed a critical control point (CCP) in the cooking process of Kaledo, i.e., at the time of boiling the meat and bones.

Sign in / Sign up

Export Citation Format

Share Document