Macrophages play an important role in host defense under several immunological, inflammatory, and/or infectious conditions. In our previous work, we demonstrated that endoplasmic reticulum aminopeptidase 1 (ERAP1) was secreted from macrophages in response to LPS and IFN-γ, and it enhanced their phagocytic activity. In this study, we analyzed the mechanism of LPS/IFN-γ-induced ERAP1 secretion. L...

Aminopeptidase T (AP-T) is a metallo-dependent dimeric enzyme of Thermus aquaticus YT-1, an extremely thermophilic bacterium. We cloned the AP-T gene from T. aquaticus YT-1 into Escherichia coli using a synthetic oligonucleotide as a hybridization probe. The nucleotide sequence of the AP-T gene was found to encode 408 amino acid residues with GTG as a start codon. The molecular weight was calcu...

The amounts of dynorphin-(1-8) [dyn-(1-8)] and its seven hydrolysis products, Y, YG, YGG, YGGF, YGGFL, YGGFLR and YGGFLRR, were estimated after incubating dyn-(1-8) with a membrane fraction from either guinea-pig ileum or striatum for various times at 37 degrees C. The major hydrolysis products during the initial 5-min incubation were YGGFLR and Y, which indicates that dipeptidyl carboxypeptida...

More than 70,000 protein structures are currently found in the Protein Data Bank, and approximately one-third contain metal ions essential for function. Identifying and characterizing metal ion–binding sites experimentally is timeconsuming and costly. Recently, the three-dimensional structure of two aminopeptidases, the methionine aminopeptidase from Escherichia coli and the leucine aminopeptid...

Aminopeptidase B (Ap-B) is a Zn2+-dependent exopeptidase which selectively removes Arg and/or Lys residues from the N terminus of several peptide substrates. Isolated and characterized from rat testes, this ubiquitous enzyme may participate in the final stages of precursor processing mechanisms. To test this hypothesis, we have investigated the secretion and subcellular localization of this enz...

BACKGROUND Snake bite is a major neglected public health issue within poor communities living in the rural areas of several countries throughout the world. An estimated 2.5 million people are bitten by snakes each year and the cost and lack of efficacy of current anti-venom therapy, together with the lack of detailed knowledge about toxic components of venom and their modes of action, and the u...

Liu H, Hu B, Huang J, Wang Q, F, Pan F and Chen L (2022) Endoplasmic Reticulum Aminopeptidase 1 Is Involved in Anti-viral Immune Response of Hepatitis B Virus by Trimming Core Antigen to Generate 9-Mers Peptides. Front. Microbiol. 13:829241. doi: 10.3389/fmicb.2022.829241 Due a production error, Reviewer was erroneously named the published article. The name has been removed.The publisher apolog...

Spark emission and atomic absorption spectroscopy of crystalline leucine aminopeptidase (bovine lens) (EC 3.4.1.1) shows the presence of 2 zinc atoms per subunit molecular weight of 54,000 (12 zinc atoms per oligomer of 320,000). Removal of zinc by dialysis yields a zinc-free product with no enzymatic activity which upon readdition of Zn2+, regains full activity with the concomitant binding of ...

Stabilizing extracellular enzymes may maintain enzymatic activity while protecting enzymes from proteolysis and denaturation. A study determined whether a fast pyrolysis hardwood biochar (CQuest™) would reduce evaporative losses, subsequently stabilizing soil extracellular enzymes and prohibiting potential enzymatic activity loss following a denaturing stress (microwaving). Soil was incubated i...

The M1 alanyl aminopeptidase from Plasmodium falciparum has been shown to be an essential hemoglobinase enzyme, catalyzing the final stages of hemoglobin break-down within intra-erythrocytic parasites 1. Recently there has been much interest in this protease as a potential drug target for the development of novel antimalarials [1-13]. In a recent report, Krishnamoorthy and Achary propose that S...