scholarly journals Effect of specific proteolytic cleavages on tubulin polymer formation

1988 ◽  
Vol 252 (3) ◽  
pp. 683-691 ◽  
Author(s):  
L Serrano ◽  
F Wandosell ◽  
J de la Torre ◽  
J Avila
Keyword(s):  
Staphylococcus Aureus ◽  
Self Assembly ◽  
Limited Proteolysis ◽  
Proteinase K ◽  
Lateral Interactions ◽  
Directional Growth ◽  
Microtubule Polymerization ◽  
Polymer Formation ◽  
Constant Polarity ◽  
Proteolytic Cleavages

The capacity for self-polymerization and shape of the tubulin polymers assembled after digestion with trypsin, Pronase, chymotrypsin, subtilisin, Staphylococcus aureus proteinase V8 and proteinase K were investigated. Digestion with trypsin, Pronase or chymotrypsin resulted in a decrease in the ability of tubulin for self-assembly, whereas limited proteolysis with subtilisin, S. aureus proteinase V8 or proteinase K resulted in an increase in such ability. The shape of the assembled polymers varied from typical microtubules (after the treatment with trypsin or Pronase) to sheets (after the treatment with chymotrypsin) and from hooked microtubules with a constant polarity (after the treatment with subtilisin) to the disappearance of a defined polarity of such polymers (after the treatment with S. aureus V8 proteinase or proteinase K). These results indicate that the tubulin C-terminal regions are involved in the regulation of microtubule polymerization, shape, directional growth and lateral interactions between tubulin protofilaments.

Detection and partial characterization of extracellular inducers of persistence in Staphylococcus epidermidis and Staphylococcus aureus

2021 ◽  
Vol 70 (6) ◽  
Author(s):  
Elyse C. Curry ◽  
Ryan G. Hart ◽  
Danni Y. Habtu ◽  
Neal R. Chamberlain
Keyword(s):  
Molecular Weight ◽  
Staphylococcus Aureus ◽  
Staphylococcus Epidermidis ◽  
Type Species ◽  
Proteinase K ◽  
Partial Characterization ◽  
Content Type ◽  
Link Type ◽  
Inducing Factors

Introduction. This study describes the identification and partial characterization of persistence-inducing factors (PIFs) from staphylococci. Hypothesis/Gap Statement. Increases in persisters during mid-log phase growth indicate that quorum-sensing factors might be produced by staphylococci. Aim. To identify and partially characterize PIFs from Staphylococcus epidermidis RP62A and Staphylococcus aureus SH1000. Methodology. Others have demonstrated a significant increase in persister numbers during mid-log phase. Inducers of this mid-log increase have yet to be identified in staphylococci. Optical density at 600 nm (OD600) was used instead of time to determine when persister numbers increased during logarithmic growth. Concentrated culture filtrates (CCFs) from S. epidermidis and S. aureus were obtained at various OD600s and following incubation at 16 h. The CCFs were used to develop a PIF assay. The PIF assay was used to partially characterize PIF from S. epidermidis and S. aureus for sizing of PIF activity, temperature and protease sensitivity and inter-species communications. Results. The optimal OD600s for S. epidermidis and S. aureus PIF assays were 2.0 and 0.5, respectively. The highest PIF activity for both species was from CCF following incubation overnight (16 h). S. epidermidis ’ PIF activity was decreased by storage at 4 oC but not at 20 oC (16 h), 37 oC (1 h) or 100 oC (15 min). S. aureus ’ PIF activity was decreased following storage at 4 oC (2 weeks) and after boiling at 100 oC for 5 min but not after incubation at 37 oC (1 h). PIF activity from both species went through a 3000 molecular weight cutoff ultrafilter. Proteinase K treatment of S. aureus PIF decreased activity but did not decrease the PIF activity of S. epidermidis . PIF from S. epidermidis did not increase persisters when used to treat S. aureus cells and nor did PIF from S. aureus increase persisters when used to treat S. epidermidis cells. Conclusions. Attempts to discover PIFs for staphylococci were unsuccessful due to the time-based means used to identify mid-log. Both staphylococcal species produce extracellular, low-molecular-weight inducers of persistence when assayed using an OD600 -based PIF assay.

scholarly journals Self-assembly of nucleopeptides to interact with DNAs

2017 ◽  
Vol 7 (6) ◽  
pp. 20160116 ◽  
Author(s):  
Xuewen Du ◽  
Jie Zhou ◽  
Xinming Li ◽  
Bing Xu
Keyword(s):  
Hydrogen Bonds ◽  
Plasmid Dna ◽  
Self Assembly ◽  
Unique Property ◽  
The Self ◽  
Proteinase K ◽  
Rational Approach ◽  
Proteolytic Resistance ◽  
Soft Biomaterials

As a novel class of biomaterials, nucleopeptides, via the conjugation of nucleobases and peptides, usually self-assemble to form nanofibres driven mainly by hydrogen bonds. Containing nucleobase(s), nucleopeptides have a unique property—interacting with nucleic acids. Here we report the design and characterization of nucleopeptides that self-assemble in water and are able to interact with single-stranded DNAs (ssDNAs). Containing nucleobases on their side chains, these nucleopeptides bind with the ssDNAs, and the ssDNAs reciprocally affect the self-assembly of nucleopeptides. In addition, the interactions between nucleopeptides and ssDNAs also decrease their proteolytic resistance against proteinase K, which further demonstrates the binding with ssDNAs. The nucleopeptides also interact with plasmid DNA and deliver hairpin DNA into cells. This work illustrates a new and rational approach to create soft biomaterials by the integration of nucleobases and peptides to bind with DNA, which may lead to the development of nucleopeptides for controlling DNA in cells.

scholarly journals Promising Antibiofilm Agents: Recent Breakthrough against Biofilm Producing Methicillin-Resistant Staphylococcus aureus

Antibiotics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 667 ◽  
Author(s):  
Marwa I. Abd El-Hamid ◽  
El-sayed Y. El-Naenaeey ◽  
Toka M kandeel ◽  
Wael A. H. Hegazy ◽  
Rasha A. Mosbah ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Agents ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Proteinase K ◽  
Zno Nps ◽  
Methicillin Resistant ◽  
Biofilm Production ◽  
Antibiofilm Agents

Multidrug resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) is a superbug pathogen that causes serious diseases. One of the main reasons for the lack of the effectiveness of antibiotic therapy against infections caused by this resistant pathogen is the recalcitrant nature of MRSA biofilms, which results in an increasingly serious situation worldwide. Consequently, the development of innovative biofilm inhibitors is urgently needed to control the biofilm formation by this pathogen. In this work, we thus sought to evaluate the biofilm inhibiting ability of some promising antibiofilm agents such as zinc oxide nanoparticles (Zno NPs), proteinase K, and hamamelitannin (HAM) in managing the MRSA biofilms. Different phenotypic and genotypic methods were used to identify the biofilm producing MDR MRSA isolates and the antibiofilm/antimicrobial activities of the used promising agents. Our study demonstrated strong antibiofilm activities of ZnO NPs, proteinase K, and HAM against MRSA biofilms along with their transcriptional modulation of biofilm (intercellular adhesion A, icaA) and quorum sensing (QS) (agr) genes. Interestingly, only ZnO NPs showed a powerful antimicrobial activity against this pathogen. Collectively, we observed overall positive correlations between the biofilm production and the antimicrobial resistance/agr genotypes II and IV. Meanwhile, there was no significant correlation between the toxin genes and the biofilm production. The ZnO NPs were recommended to be used alone as potent antimicrobial and antibiofilm agents against MDR MRSA and their biofilm-associated diseases. On the other hand, proteinase-K and HAM can be co-administrated with other antimicrobial agents to manage such types of infections.

Self-Assembly Directed Organization of Nanodiamond During Ionic Liquid Crystalline Polymer Formation

2016 ◽  
Vol 37 (14) ◽  
pp. 1155-1167 ◽  
Author(s):  
Bryan S. Ringstrand ◽  
Sönke Seifert ◽  
David W. Podlesak ◽  
Millicent A. Firestone
Keyword(s):  
Ionic Liquid ◽  
Self Assembly ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Polymer Formation

scholarly journals Highly exposed segment of the Spf1p P5A-ATPase near transmembrane M5 detected by limited proteolysis

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245679
Author(s):  
Guido D. Petrovich ◽  
Gerardo R. Corradi ◽  
Carlos H. Pavan ◽  
Sofia Noli Truant ◽  
Hugo P. Adamo
Keyword(s):  
Atpase Activity ◽  
Metal Ion ◽  
Limited Proteolysis ◽  
Large Family ◽  
Proteinase K ◽  
Short Exposure ◽  
Transmembrane Segments ◽  
D Region ◽  
Group 5 ◽  
A Minor

The yeast Spf1p protein is a primary transporter that belongs to group 5 of the large family of P-ATPases. Loss of Spf1p function produces ER stress with alterations of metal ion and sterol homeostasis and protein folding, glycosylation and membrane insertion. The amino acid sequence of Spf1p shows the characteristic P-ATPase domains A, N, and P and the transmembrane segments M1-M10. In addition, Spf1p exhibits unique structures at its N-terminus (N-T region), including two putative additional transmembrane domains, and a large insertion connecting the P domain with transmembrane segment M5 (D region). Here we used limited proteolysis to examine the structure of Spf1p. A short exposure of Spf1p to trypsin or proteinase K resulted in the cleavage at the N and C terminal regions of the protein and abrogated the formation of the catalytic phosphoenzyme and the ATPase activity. In contrast, limited proteolysis of Spf1p with chymotrypsin generated a large N-terminal fragment containing most of the M4-M5 cytosolic loop, and a minor fragment containing the C-terminal region. If lipids were present during chymotryptic proteolysis, phosphoenzyme formation and ATPase activity were preserved. ATP slowed Spf1p proteolysis without detectable changes of the generated fragments. The analysis of the proteolytic peptides by mass spectrometry and Edman degradation indicated that the preferential chymotryptic site was localized near the cytosolic end of M5. The susceptibility to proteolysis suggests an unexpected exposure of this region of Spf1p that may be an intrinsic feature of P5A-ATPases.

scholarly journals Production and Extraction Of Antibacterial Bacteriocin from Pediococcus sp. NWD 015

2015 ◽  
Vol 11 (2) ◽  
Author(s):  
N. Nofisulastri ◽  
Zaenal Bachruddin ◽  
Eni Harmayani
Keyword(s):  
Heat Treatment ◽  
Molecular Weight ◽  
Staphylococcus Aureus ◽  
Listeria Monocytogenes ◽  
Enterococcus Faecalis ◽  
Storage Time ◽  
Bacteriocin Production ◽  
Proteinase K ◽  
Bacteriocin Activity

objectives were to study the growth pattern of Pediococcus sp. NWD 015 and bacteriocin activity, extractionand characterization of bacteriocin, and to determine the effect of storage time and temperature on bacteriocinactivity. Results showed that the bacteriocin activity increased during growth and reached the highest activity duringstationary phase. The maximum bacteriocin production reached after incubation of the cell for 12 h at 37oC in TGEbroth and decreased after 96 h incubation. Extraction with adsorbtion-desorbtion method could increased a specificactivity of bacteriocin. Bacteriocin from Pediococcus sp. NWD 015 is inactivated by Proteinase-K; however it is stillactive by heat treatment at 121oC for 15 min and over pH 2 – 11. Bacteriocin of Pediococcus sp. NWD 015 was effectiveagaints Enterococcus faecalis, Staphylococcus aureus, Eschericia coli, Listeria monocytogenes but not against Salmonellathypimurium. The molecular weight of bacteriocin is 4.95 kDa.Keywords : Bacteriocins, Pediococcus sp NWD 015.

scholarly journals Cross-talk between individual phenol-soluble modulins in Staphylococcus aureus biofilm enables rapid and efficient amyloid formation

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Masihuz Zaman ◽  
Maria Andreasen
Keyword(s):  
Staphylococcus Aureus ◽  
Self Assembly ◽  
Biofilm Formation ◽  
Opportunistic Pathogen ◽  
Amyloid Formation ◽  
Secondary Nucleation ◽  
Primary Nucleation ◽  
Functional Amyloids ◽  
High Degree

The infective ability of the opportunistic pathogen Staphylococcus aureus, recognized as the most frequent cause of biofilm-associated infections, is associated with biofilm-mediated resistance to host immune response. Phenol-soluble modulins (PSM) comprise the structural scaffold of S. aureus biofilms through self-assembly into functional amyloids, but the role of individual PSMs during biofilm formation remains poorly understood and the molecular pathways of PSM self-assembly are yet to be identified. Here we demonstrate high degree of cooperation between individual PSMs during functional amyloid formation. PSMα3 initiates the aggregation, forming unstable aggregates capable of seeding other PSMs resulting in stable amyloid structures. Using chemical kinetics we dissect the molecular mechanism of aggregation of individual PSMs showing that PSMα1, PSMα3 and PSMβ1 display secondary nucleation whereas PSMβ2 aggregates through primary nucleation and elongation. Our findings suggest that various PSMs have evolved to ensure fast and efficient biofilm formation through cooperation between individual peptides.

scholarly journals Enhanced Treatment Effects of Tilmicosin Against Staphylococcus aureus Cow Mastitis by Self-Assembly Sodium Alginate-Chitosan Nanogel

Pharmaceutics ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 524 ◽  
Author(s):  
Kaixiang Zhou ◽  
Xiaofang Wang ◽  
Dongmei Chen ◽  
Yuanyuan Yuan ◽  
Shuge Wang ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Self Assembly ◽  
In Vitro Release ◽  
Physicochemical Characteristics ◽  
The Novel ◽  
In Situ Hydrogel ◽  
Treatment Dosage ◽  
Normal Dosage

The Staphylococcus aureus (S. aureus) cow mastitis causes great losses to the cow industry. In order to improve the treatment effect of tilmicosin against cow mastitis, the combination of solid lipid nanoparticle (SLN) technology with in situ hydrogel technology was used to prepare the self-assembly tilmicosin nanogel (TIL-nanogel). The physicochemical characteristics, in vitro release, antibacterial activity and in vivo treatment efficacy of TIL-SLNs and TIL-nanogel were studied, respectively. The results showed the loading capacity (LC), encapsulation efficiency (EE), size, zeta potential and poly dispersion index (PDI) of TIL-nanogel were 23.33 ± 0.77%, 67.89 ± 3.01%, 431.57 ± 12.87 nm, 8.3 ± 0.06 mv and, 0.424 ± 0.032, respectively. The TIL-nanogel showed stronger sustained release in vitro than TIL-SLNs and commercial injection. The cure rate of half dosage and normal dosage of TIL-nanogel was 58.3% and 75.0%, which was higher than that of commercial injection (50.0%) at normal dosage. The results suggest that the treatment dosage of tilmicosin for cow mastitis could be reduced by TIL-nanogel. The novel TIL-nanogel will be beneficial by decreasing the usage of tilmicosin and the treatment costs of cow mastitis.

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