We report a hybrid quantum mechanics/molecular mechanics theoretical study on the reaction mechanism of mammalian histidine decarboxylase that allows us to obtain valuable insights on the structure of the cofactor-substrate adduct (external aldimine) in the active site of rat histidine decarboxylase. By means of molecular dynamics simulations, we traced the potential of mean force corresponding to the decarboxylation reaction of the adduct both in the active site of the enzyme and in aqueous solution. By comparing this process in both media, we have identified the key electrostatic interactions that explain the lowering of the free energy barrier in the enzyme. Our analysis also offers a validation of Dunathan's hypothesis (Dunathan, H. (1966) Proc. Natl. Acad. Sci. U. S. A. 55, 712-716) regarding the role of stereoelectronic effects in the enzymatic decarboxylation process.
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http://dx.doi.org/10.1074/jbc.M707434200 | DOI Listing |
Front Pharmacol
December 2024
Fengxian Hospital, School of Pharmaceutical Sciences, Southern Medical University, Shanghai, China.
Objective: This study aimed to investigate the underlying mechanism of chronic stress promoting ovarian cancer growth comorbid with depression and evaluate the potential role of histamine (HIS) in treating this comorbidity.
Methods: Chronic unpredictable mild stress (CUMS) was used to establish a comorbid mouse model of ovarian cancer and depression. The behavioral phenotypes were assessed using the sucrose preference test (SPT), tail suspension test (TST), forced swimming test (FST), and open field test (OFT).
Int J Food Microbiol
December 2024
College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; Engineering Research Center of Food Thermal-processing Technology, Shanghai Ocean University, Shanghai 201306, China; Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation, Shanghai 201306, China. Electronic address:
In this study, we first verified the feasibility of using Antarctic krill as a raw material for quick-brewed fish sauce, and the results showed that the amino acid nitrogen (AAN)and total soluble nitrogen(TSN) in the fermented 30 days fish sauce met the national level fish sauce standards, but the histamine content exceeded the maximum limit value of histamine in fish sauce (400 mg/kg) set by the International Codex Alimentarius Commission (CAC) and the European Union (EU). On this basis, the correlation between physicochemical indexes and bacterial communities during the fermentation of fish sauce was investigated using high-throughput sequencing, culture method. The correlation analyses revealed the relationship between bacterial communities and the quality and safety of fish sauce, and these studies will be helpful for the development of Antarctic krill fish sauce.
View Article and Find Full Text PDFBackground And Aim: The European pilchard () is an important fish species for the Moroccan economy in terms of production and export. Biogenic amine histamine is a metabolite produced in the flesh of some fish species after death due to the decarboxylation of free histidine by histaminogenic bacteria. Failure to control the histamine risk in European pilchard may lead to public health and socioeconomic issues.
View Article and Find Full Text PDFInt J Gynecol Pathol
October 2024
Department of Pathology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, Suzhou, Jiangsu, P.R. China.
Invasive stratified mucin-producing carcinoma (ISMC) is a specific type of adenocarcinoma of the cervix, which is associated with human papillomavirus infection and often coexists with other types of carcinomas. However, given its rarity, understanding of this disease remains insufficient. We present a unique case of ISMC of the cervix coexisting with a high-grade squamous intraepithelial lesion (HSIL).
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