scholarly journals Identification and Characterization of ShSPI, a Kazal-Type Elastase Inhibitor from the Venom of Scolopendra Hainanum

Toxins ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 708
Author(s):  
Ning Luan ◽  
Qiyu Zhao ◽  
Zilei Duan ◽  
Mengyao Ji ◽  
Meichen Xing ◽  
...  
Keyword(s):  
Human Neutrophils ◽  
Inhibitory Effects ◽  
Elastase Inhibitor ◽  
Endogenous Inhibitors ◽  
Venom Glands ◽  
Functional Peptides ◽  
20 Nm ◽  
Identification And Characterization ◽  
Cardiopulmonary System

Elastase is a globular glycoprotein and belongs to the chymotrypsin family. It is involved in several inflammatory cascades on the basis of cleaving the important connective tissue protein elastin, and is strictly regulated to a balance by several endogenous inhibitors. When elastase and its inhibitors are out of balance, severe diseases will develop, especially those involved in the cardiopulmonary system. Much attention has been attracted in seeking innovative elastase inhibitors and various advancements have been taken on clinical trials of these inhibitors. Natural functional peptides from venomous animals have been shown to have anti-protease properties. Here, we identified a kazal-type serine protease inhibitor named ShSPI from the cDNA library of the venom glands of Scolopendra hainanum. ShSPI showed significant inhibitory effects on porcine pancreatic elastase and human neutrophils elastase with Ki values of 225.83 ± 20 nM and 12.61 ± 2 nM, respectively. Together, our results suggest that ShSPI may be an excellent candidate to develop a drug for cardiopulmonary diseases.

scholarly journals Characterization of aStaphylococcus aureusSurface Virulence Factor That Promotes Resistance to Oxidative Killing and Infectious Endocarditis

2010 ◽  
Vol 79 (1) ◽  
pp. 342-352 ◽  
Author(s):  
Natalia Malachowa ◽  
Petra L. Kohler ◽  
Patrick M. Schlievert ◽  
Olivia N. Chuang ◽  
Gary M. Dunny ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Hypothetical Protein ◽  
Cell Number ◽  
Deletion Strain ◽  
Human Neutrophils ◽  
Bacterial Cell Number ◽  
Hospital Acquired ◽  
Identification And Characterization

ABSTRACTStaphylococcus aureusis a prominent human pathogen and a leading cause of community- and hospital-acquired bacterial infections worldwide. Herein, we describe the identification and characterization of theS. aureus67.6-kDa hypothetical protein, named for thesurface factor promoting resistance tooxidativekilling (SOK) in this study. Sequence analysis showed that the SOK gene is conserved in all sequencedS. aureusstrains and homologous to the myosin cross-reactive antigen ofStreptococcus pyogenes.Immunoblotting and immunofluorescence analysis showed that SOK was copurified with membrane fractions and was exposed on the surface ofS. aureusNewman and RN4220. Comparative analysis of wild-typeS. aureusand an isogenic deletion strain indicated that SOK contributes to both resistance to killing by human neutrophils and to oxidative stress. In addition, theS. aureus sokdeletion strain showed dramatically reduced aortic valve vegetation and bacterial cell number in a rabbit endocarditis model. These results, plus the suspected role of the streptococcal homologue in certain diseases such as acute rheumatic fever, suggest that SOK plays an important role in cardiovascular and other staphylococcal infections.

Identification and characterization of a novel Mn–N nitride formed in Fe–Mn–N alloy

2003 ◽  
Vol 36 (1) ◽  
pp. 103-108 ◽  
Author(s):  
M. Gouné ◽  
A. Redjaïmia ◽  
T. Belmonte ◽  
H. Michel
Keyword(s):  
Crystal Structure ◽  
Theory Analysis ◽  
Ferritic Matrix ◽  
Tetragonal System ◽  
Phase Crystal ◽  
20 Nm ◽  
New Phase ◽  
Identification And Characterization ◽  
Electron Microdiffraction

An unexpected phase, formed throughout the ferritic matrix of an Fe–Mn (1.62 wt% Mn) alloy during a nitriding treatment at 843 K for 8 h, is analysed. This new phase, labelled θ′, is a metastable Mn nitride. It adopts the form of plates, with length 200 nm and width 20 nm. Its crystal structure is established by electron microdiffraction in conjunction with group-theory analysis. This nitride crystallizes in the tetragonal system and belongs to the space groupP 42/m 2/m 2/cwith the following lattice parameters: a_{\theta'} = 2.876 Å and c_{\theta'} = 5.752 Å. The θ′-phase crystal lattice is oriented with respect to the surrounding ferritic matrix according to the cube-on-cube orientation relationship, namely: (100)_{\theta'} || (200)_\alpha, (010)_{\theta'} || (020)_\alpha and (002)_{\theta'} || (002)_\alpha.

scholarly journals Identification and Characterization of Mutations Conferring Resistance to d-Amino Acids in Bacillus subtilis

2015 ◽  
Vol 197 (9) ◽  
pp. 1632-1639 ◽  
Author(s):  
Sara A. Leiman ◽  
Charles Richardson ◽  
Lucy Foulston ◽  
Alexander K. W. Elsholz ◽  
Eric A. First ◽  
...  
Keyword(s):  
Amino Acids ◽  
Bacillus Subtilis ◽  
Protein Biosynthesis ◽  
Trna Synthetase ◽  
Inhibitory Effects ◽  
Content Type ◽  
Growth Inhibitory ◽  
Spontaneous Mutants ◽  
Identification And Characterization

ABSTRACTBacteria produced-amino acids for incorporation into the peptidoglycan and certain nonribosomally produced peptides. However,d-amino acids are toxic if mischarged on tRNAs or misincorporated into protein. Common strains of the Gram-positive bacteriumBacillus subtilisare particularly sensitive to the growth-inhibitory effects ofd-tyrosine due to the absence ofd-aminoacyl-tRNA deacylase, an enzyme that prevents misincorporation ofd-tyrosine and otherd-amino acids into nascent proteins. We isolated spontaneous mutants ofB. subtilisthat survive in the presence of a mixture ofd-leucine,d-methionine,d-tryptophan, andd-tyrosine. Whole-genome sequencing revealed that these strains harbored mutations affecting tRNATyrcharging. Three of the most potent mutations enhanced the expression of the gene (tyrS) for tyrosyl-tRNA synthetase. In particular, resistance was conferred by mutations that destabilized the terminator hairpin of thetyrSriboswitch, as well as by a mutation that transformed a tRNAPheinto atyrSriboswitch ligand. The most potent mutation, a substitution near the tyrosine recognition site of tyrosyl-tRNA synthetase, improved enzyme stereoselectivity. We conclude that these mutations promote the proper charging of tRNATyr, thus facilitating the exclusion ofd-tyrosine from protein biosynthesis in cells that lackd-aminoacyl-tRNA deacylase.IMPORTANCEProteins are composed ofl-amino acids. Mischarging of tRNAs withd-amino acids or the misincorporation ofd-amino acids into proteins causes toxicity. This work reports on mutations that confer resistance tod-amino acids and their mechanisms of action.

scholarly journals d-Amino Acids in Plants: Sources, Metabolism, and Functions

2020 ◽  
Vol 21 (15) ◽  
pp. 5421
Author(s):  
Üner Kolukisaoglu
Keyword(s):  
Amino Acids ◽  
Side Reactions ◽  
Inhibitory Effects ◽  
Physiological Processes ◽  
Long Time ◽  
Critical Revision ◽  
Metabolizing Enzyme ◽  
First Time ◽  
Identification And Characterization

Although plants are permanently exposed to d-amino acids (d-AAs) in the rhizosphere, these compounds were for a long time regarded as generally detrimental, due to their inhibitory effects on plant growth. Recent studies showed that this statement needs a critical revision. There were several reports of active uptake by and transport of d-AAs in plants, leading to the question whether these processes happened just as side reactions or even on purpose. The identification and characterization of various transporter proteins and enzymes in plants with considerable affinities or specificities for d-AAs also pointed in the direction of their targeted uptake and utilization. This attracted more interest, as d-AAs were shown to be involved in different physiological processes in plants. Especially, the recent characterization of d-AA stimulated ethylene production in Arabidopsis thaliana revealed for the first time a physiological function for a specific d-AA and its metabolizing enzyme in plants. This finding opened the question regarding the physiological or developmental contexts in which d-AA stimulated ethylene synthesis are involved in. This question and the ones about the transport characteristics of d-AAs, their metabolism, and their different physiological effects, are the focus of this review.

Inhibitory effects of luteolin and its derivatives on osteoclast differentiation and differences in luteolin production by Capsicum annuum varieties

2021 ◽  
Author(s):  
Shintaro Onishi ◽  
Shinichi Tebayashi ◽  
Yasufumi Hikichi ◽  
Hiromasa Sawada ◽  
Yukiko Ishii ◽  
...  
Keyword(s):  
Capsicum Annuum ◽  
Osteoclast Differentiation ◽  
Inhibitory Effect ◽  
Plant Residue ◽  
Plant Residues ◽  
Inhibitory Effects ◽  
Effective Development ◽  
Osteoclastic Differentiation ◽  
Identification And Characterization

ABSTRACT Luteolin, an abundant flavonoid in the leaves of Capsicum annuum, has antioxidant activity and is, thus, a key chemical for promoting plant residue utilization, especially for the development of healthcare products. We assessed the inhibitory effect of luteolin and its glycosides on osteoclastic differentiation in human cells and found that the differentiation was effectively inhibited at noncytotoxic concentrations. We also screened 47 varieties of C. annuum for the accumulation of luteolin and apigenin to determine the prevalence of luteolin in diverse cultivars and identify varieties with high and/or selective luteolin production. The glycosides of luteolin and apigenin were found in all the tested varieties, with luteolin predominant over apigenin in most varieties. The identification and characterization of highly productive varieties of C. annuum is expected to be beneficial for the effective development of useful luteolin-based products from plant residues.

Sign in / Sign up

Export Citation Format

Share Document