A Potent Antimicrobial Peptide Derived from the Protein LsGRP1 of Lilium

Abstract

LsGRP1 is a defense-related gene differentially expressed in lily leaves in response to pathogen attack. The difficulty in the expression of LsGRP1 in Escherichia coli suggested the presence of antimicrobial activity in LsGRP1. To evaluate the antimicrobial trait of LsGRP1, three LsGRP1-derived peptides were chemically synthesized; namely LsGRP1(N) (N-terminal region without the signal peptide), LsGRP1(G) (glycine-rich region), and LsGRP1(C) (C-terminal cysteine-rich region). LsGRP1(C) was proposed to be a potential antimicrobial agent according to its broad-spectrum and effective antimicrobial activity. LsGRP1(C) displayed inhibition effects on bacterial and fungal growth, possibly by altering the integrity of the cell membrane, as indicated by scanning electron microscopy and SYTOX Green staining assays. Additionally, LsGRP1(C) induced programmed cell death-like phenomenon in the tested fungal species as indicated by 2',7'-dichlorodihydrofluorescein diacetate and 4',6'-diamidino-2-phenylindole assays. Further immunofluorescence staining showed that LsGRP1(C) was located at the fungal cell surface. According to these observations, we concluded that LsGRP1(C) originated from the plant defense-related protein LsGRP1 would play a role as an antimicrobial peptide and have a potential for practical use.

Design of novel peptide inhibitors against the conserved bacterial transcription terminator, Rho

“…In a different approach, synthetic AMPs were also synthesized from the naturally occurring antimicrobials. AWRK6 is a synthetic peptide that was derived from the frog-skin antimicrobial Dybowskin-2CDYa ( 30 ), several potent AMPs were produced from the plant antimicrobial protein LsGRP1 of Lilium ( 31 ) and the synthetic peptide In-58 was derived from indolicidin ( 32 ). Functional peptides were also designed based on the structures of HIV-1 protein gp120, chemotaxis inhibitory protein of Staphylococcus aureus ( 33 , 34 , 35 ), and so forth.…”

Lilium Gray Mold Suppression Conferred by the Host Antimicrobial Protein LsGRP1 Involves Main Pathogen-Targeted Manipulation of the Nonantimicrobial Region LsGRP1N

“…Spore suspensions of 5 × 10 4 spores mL –1 were treated with peptides or proteins, and the inhibition rate and half-maximal inhibitory concentration (IC 50 ) against spore germination of peptide or protein treatment were calculated following the description by Lin et al Because the spore germination of B. elliptica could be triggered upon water alone, akin to Aspergillus niger, 0, 1, and 0.5% glucose was applied to the assays of B.…”

“…LsGRP1 features the typical structure of class II GRPs, consisting of a signal sequence LsGRP1 SS , a N-terminal uncharacterized LsGRP1 N region, a central glycine-rich LsGRP1 G region, and a C-terminal cysteine-rich LsGRP1 C region. LsGRP1 C , as an antimicrobial region, endows LsGRP1 with antimicrobial activity by causing microbial membrane permeabilization and fungal PCD, ,, as the most common mechanisms of antimicrobial peptides. , Removal of LsGRP1 C fully abolished the fungal PCD-eliciting function of LsGRP1 in the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay for PCD detection, and the B. elliptica PCD-eliciting activity of LsGRP1 was superior to that of LsGRP1 C at the same molar concentration (10 μM) by 14% .…”

“…CWDEs of necrotrophic fungi are important virulence factors. In turn, hosts may recognize some CWDEs and cell-wall-degrading products, such as OGs, to trigger immune activation. , Because pectin-associated LsGRP1 is the only plant class II GRP proven to directly hurt fungal invaders, ,, whether it also affects pathogen behaviors, such as CWDE expression and host immune elicitation, aroused our curiosity.…”

Collection of antimicrobial peptides database and its derivatives: Applications and beyond

“…The AMP prediction algorithm, available through CAMP, has been successfully used to identify/predict peptides with antimicrobial activity from natural sources such as Protaetia brevitarsis larvae, Sichuan pepper, Litopenaeus vannamei , milk proteins, human sweat, Thermophilic geobacillus sp. Strain ZGt‐1, Varanus komodoensis (Komodo Dragon), American alligator plasma, human basal tear sample, Oxya chinensis sinuosa (grasshopper), lily leaves, Chrysochromulina tobin , and marine mussels . Few of these peptides have been experimentally validated using wet‐lab methods.…”