scholarly journals Engineering dehydrated amino acid residues in the antimicrobial peptide nisin.

1992 ◽  
Vol 267 (34) ◽  
pp. 24340-24346
Author(s):  
O.P. Kuipers ◽  
H.S. Rollema ◽  
W.M. Yap ◽  
H.J. Boot ◽  
R.J. Siezen ◽  
...  
Keyword(s):  
Amino Acid ◽  
Antimicrobial Peptide ◽  
Amino Acid Residues

scholarly journals Identifying and Characterizing a Novel Peritrophic Matrix Protein (MdPM-17) Associated With Antibacterial Response From the Housefly, Musca domestica (Diptera: Muscidae)

2020 ◽  
Vol 20 (6) ◽  
Author(s):  
Yu Wang ◽  
Jinzhi Cheng ◽  
Man Luo ◽  
Jianwei Wu ◽  
Guo Guo
Keyword(s):  
Amino Acid ◽  
Antimicrobial Peptide ◽  
Musca Domestica ◽  
Matrix Protein ◽  
Binding Capacity ◽  
Malpighian Tubule ◽  
Peritrophic Membrane ◽  
Distribution Analysis ◽  
Peritrophic Matrix ◽  
Amino Acid Residues

Abstract Peritrophic matrix/membrane (PM) critically prevents the midgut of insects from external invasion by microbes. The proteins in the peritrophic membrane are its major structural components. Additionally, they determine the formation and function of this membrane. However, the role of PM proteins in immune regulation is unclear. Herein, we isolated a novel PM protein (MdPM-17) from Musca domestica larvae. Further, the function of MdPM-17 in regulating host innate immunity was identified. Results showed that the cDNA of MdPM-17 full is 635 bp in length. Moreover, it consists of a 477-bp open reading frame encoding 158 amino acid residues. These amino acid residues are composed of two Chitin-binding type-2 domain (ChtBD2) and 19 amino acids as a signal peptide. Moreover, tissue distribution analysis indicates that MdPM-17 was enriched expressed in midgut, and moderate levels in the fat body, foregut, and malpighian tubule. Notably, MdPM-17 recombinant protein showed high chitin-binding capacity, thus belongs to the Class III PM protein group. MdPM-17 protein silencing via RNA interference resulted in the expression of antimicrobial peptide (defensin, cecropins, and diptericin) genes, and this occurred after oral inoculation with exogenous microbes Escherichia coli (Enterobacteriales:Enterobacteriaceae), Staphylococcus aureus (Bacillales:Staphylococcaceae), and Candida albicans (Endomycetales:Saccharomycetaceae)). Therefore, all the antimicrobial peptide (AMP) gene expression levels are high in MdPM-17-depleted larvae during microbial infection compared to controls. Consequently, these findings indicate that MdPM-17 protein is associated with the antibacterial response from the housefly.

Substrate Recognition by Vitamin K-Dependent Carboxylase

1987 ◽  
Vol 57 (01) ◽  
pp. 017-019 ◽  
Author(s):  
Magda M W Ulrich ◽  
Berry A M Soute ◽  
L Johan M van Haarlem ◽  
Cees Vermeer
Keyword(s):  
Amino Acid ◽  
Vitamin K ◽  
Substrate Recognition ◽  
Bovine Liver ◽  
Amino Acid Residues

SummaryDecarboxylated osteocalcins were prepared and purified from bovine, chicken, human and monkey bones and assayed for their ability to serve as a substrate for vitamin K-dependent carboxylase from bovine liver. Substantial differences were observed, especially between bovine and monkey d-osteocalcin. Since these substrates differ only in their amino acid residues 3 and 4, it seems that these residues play a role in the recognition of a substrate by hepatic carboxylase.

Statistical Force-Field for Structural Modeling Using Chemical Cross-Linking/mass Spectrometry Distance Constraints

2018 ◽  
Author(s):  
Allan J. R. Ferrari ◽  
Fabio C. Gozzo ◽  
Leandro Martinez
Keyword(s):  
Mass Spectrometry ◽  
Amino Acid ◽  
Force Field ◽  
Protein Structures ◽  
Protein Structure Determination ◽  
Structural Modeling ◽  
Cross Linking ◽  
Amino Acid Residues ◽  
Distance Constraints ◽  
Chemical Cross Linking

<div><p>Chemical cross-linking/Mass Spectrometry (XLMS) is an experimental method to obtain distance constraints between amino acid residues, which can be applied to structural modeling of tertiary and quaternary biomolecular structures. These constraints provide, in principle, only upper limits to the distance between amino acid residues along the surface of the biomolecule. In practice, attempts to use of XLMS constraints for tertiary protein structure determination have not been widely successful. This indicates the need of specifically designed strategies for the representation of these constraints within modeling algorithms. Here, a force-field designed to represent XLMS-derived constraints is proposed. The potential energy functions are obtained by computing, in the database of known protein structures, the probability of satisfaction of a topological cross-linking distance as a function of the Euclidean distance between amino acid residues. The force-field can be easily incorporated into current modeling methods and software. In this work, the force-field was implemented within the Rosetta ab initio relax protocol. We show a significant improvement in the quality of the models obtained relative to current strategies for constraint representation. This force-field contributes to the long-desired goal of obtaining the tertiary structures of proteins using XLMS data. Force-field parameters and usage instructions are freely available at http://m3g.iqm.unicamp.br/topolink/xlff <br></p></div><p></p><p></p>

Sign in / Sign up

Export Citation Format

Share Document