scholarly journals Characterization of the ςB Regulon inStaphylococcus aureus

2000 ◽  
Vol 182 (24) ◽  
pp. 6983-6991 ◽  
Author(s):  
Silke Gertz ◽  
Susanne Engelmann ◽  
Roland Schmid ◽  
Anne-Kathrin Ziebandt ◽  
Karsten Tischer ◽  
...  
Keyword(s):  
Protein Pattern ◽  
Physiological Role ◽  
Positive Control ◽  
Homologous Gene ◽  
Gram Negative Bacteria ◽  
Transport Mechanisms ◽  
Stress Genes ◽  
Gram Positive Bacteria ◽  
Cytoplasmic Proteins

ABSTRACT The ςB-dependent stress regulon in gram-positive bacteria might fulfill a physiological role in stress response and virulence similar to that of the ςS regulon inEscherichia coli and other gram-negative bacteria. In order to obtain evidence for the function of the ςB regulon ofStaphylococcus aureus, especially in virulence control, ςB-dependent stress genes were identified. The two-dimensional protein pattern of wild-type cells of S. aureus COL was compared with that of an isogenic sigBmutant. By this approach, we found that the synthesis of about 27 cytoplasmic proteins seemed to be under the positive control of ςB. N-terminal sequencing of 18 proteins allowed the identification of their genes on the almost finished genome sequence ofS. aureus COL and the analysis of the promoter structure. Transcriptional analyses of 11 of these genes confirmed their ςB dependency, and moreover, about 7 additional ςB-dependent genes were found which are cotranscribed with the newly detected genes, forming operons. Altogether, we identified 23 ςB-dependent genes and their corresponding proteins. Among them are proteins probably involved in the generation of NADH or in membrane transport mechanisms. Furthermore, at least oneclpC-homologous gene was localized on the S. aureus sequence solely transcribed by ςB. In contrast, a second clpC-homologous gene in S. aureus forming an operon with ctsR, yacH, and yacI was ςB independently expressed.

Antimicrobial activity of Pycnarrhena cauliflora (Miers.) Diels. methanol extract

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Eti Nurwening Sholikhah ◽  
Maulina Diah ◽  
Mustofa ◽  
Masriani ◽  
Susi Iravati ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Methanolic Extract ◽  
Biological Activities ◽  
Positive Control ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Methanolic Extracts

Pycnarrhena cauliflora (Miers.) Diels., local name sengkubak, is one of indigenous plants from West Kalimantan that has been used as natural flavor. Pycnorrhena cauliflora is one of species of Menispermaceae family which is rich in bisbenzylisoquinoline alkaloids. This alkaloids are known to have various biological activities including antiprotozoal, antiplasmodial, antifungal and antibacterial activities. This study aimed to investigate antimicrobial activity of  the P. cauliflora (Miers.) Diels. methanolic extracts against gram-positive and gram-negative bacteria. The methanolic extract of P. cauliflora (Miers.) Diels., root, leaf and stem were prepared by maceration. The disk-diffusion method was then used to determine the antimicrobial activity of the extracts against Streptococcus pyogenes, S. mutants, Staphylococcus aureus, S. epidermidis, Salmonella typhi, Shigella flexneri, Pseudomonas aeruginosa and Escherichia coli after 18-24 h incubation at 37 oC. Amoxicillin was used as positive control for gram-positive bacteria and ciprofloxacin was used as gram-negative bacteria. The inhibition zones were then measured in mm. Analysis were conducted in duplicates. The results showed in general the methanolic extracts of P. cauliflora (Miers.) Diels. root (inhibition zone diameter= 10-23 mm) were more active than that leaf (0-15 mm) and stem (0-17 mm) extracts against gram-positive bacteria. The zone inhibition diameter of amoxicillin as positive control was 8-42 mm. In addition, the methanolic extracts of P. cauliflora (Miers.) Diels. root (12-17 mm) were also more active than that leaf (0-12 mm) and stem (0-12 mm) extracts against gram-negative bacteria. The zone inhibition diameter of ciprofloxacin as positive control was 33-36 mm. In conclusion, the methanolic extract of P. caulifloria (Miers.) Diels. root is the most extract active against both gram-positive and gram-negative bacteria. Further study will be focused to isolate active compounds in the methanolic extract of the root.

scholarly journals SKRENING BAKTERI TOLERAN PESTISIDA DENGAN BAHAN AKTIF KLORANTRANILIPROL ASAL TANAH PERTANIAN BATURITI TABANAN BALI

2017 ◽  
Vol 21 (1) ◽  
pp. 1
Author(s):  
NI KADEK WIWIK SINTA DEWI ◽  
IDA BAGUS GEDE DARMAYASA ◽  
I KETUT SUNDRA
Keyword(s):  
Large Scale ◽  
Chemical Compounds ◽  
Mineral Medium ◽  
Gram Negative Bacteria ◽  
Soil Mineral ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Numerous Problem ◽  
Stage 1

In Indonesia agriculture practice often used the large scale pesticide application such as insecticide, herbicide, and fungicide. The wide use of toxic pesticide has created numerous problem in increasing environtmental hazard to human and to other animals. Many of soil bacteria had important role to degrading chemical compounds into simpler compounds as a bioremediation agent. The aim of this study was to screen the Chlorantraniliprole tolerant bacteria using soil mineral medium with Prevathon pesticide addition, also teo identificate the species of bacteria. This research was conducted at Microbiology Laboratory, Faculty of Mathematics and Natural Sciences, Udayana University. The research was done in three analysis, (1) bacteria test on Prevathon pesticide addition to mineral medium treatment, (2) characterization of bacteria, (3) Identification of pesticide tolerant bacteria with BD BBL Crystal Enteric/Non FermenterID Kit. The results showed that mineral medium with the addition of pesticides Prevathon treatment able to provide a significant different effect on the enrichment stage 1, stage 2 and stage 3 (P<0.05), there was 5 isolates pesticide tolerant bacteria that isolated from Baturiti Tabanan cultivated soil that was BSP 1, BSP 2, BSP 3 known as gram negative bacteria, and BSP 4, BSP 5 known as Gram positive bacteria, pesticide tolerant bacteria identified as Serratia marcescens which is a Gram negative bacteria group and may cause pathogenic.

scholarly journals Insights into AMS/PCAT transporters from biochemical and structural characterization of a double Glycine motif protease

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Silvia C Bobeica ◽  
Shi-Hui Dong ◽  
Liujie Huo ◽  
Nuria Mazo ◽  
Martin I McLaughlin ◽  
...  
Keyword(s):  
Structural Data ◽  
Leader Peptide ◽  
Gram Negative Bacteria ◽  
Protease Domain ◽  
Peptide Recognition ◽  
Gram Positive Bacteria ◽  
Dual Functional ◽  
Signaling Peptides

The secretion of peptides and proteins is essential for survival and ecological adaptation of bacteria. Dual-functional ATP-binding cassette transporters export antimicrobial or quorum signaling peptides in Gram-positive bacteria. Their substrates contain a leader sequence that is excised by an N-terminal peptidase C39 domain at a double Gly motif. We characterized the protease domain (LahT150) of a transporter from a lanthipeptide biosynthetic operon in Lachnospiraceae and demonstrate that this protease can remove the leader peptide from a diverse set of peptides. The 2.0 Å resolution crystal structure of the protease domain in complex with a covalently bound leader peptide demonstrates the basis for substrate recognition across the entire class of such transporters. The structural data also provide a model for understanding the role of leader peptide recognition in the translocation cycle, and the function of degenerate, non-functional C39-like domains (CLD) in substrate recruitment in toxin exporters in Gram-negative bacteria.

Synthesis, Characterization, and Antibacterial Evaluation of Curcumin-Sulfanilamide Compound

2020 ◽  
Vol 840 ◽  
pp. 265-269
Author(s):  
Nurjanah Nurjanah ◽  
Endang Saepudin
Keyword(s):  
Antibacterial Activity ◽  
Functional Group ◽  
Biological Activities ◽  
Curcuma Longa ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Ftir Spectrophotometry

Curcumin, a diarylheptanoids compound which isolated primary from Curcuma longa, exhibits a variety of exciting biological activities, including as an antibacterial agent. In the present study, a sulfanilamide-contained curcumin compound was synthesized and characterized to investigate the antibacterial activity against gram-positive bacteria S. aureus, B. subtilis and gram-negative bacteria E. coli. The characterization of the synthesized compound was determined by analysing peak absorbance, functional group, and molecular weight using mass spectroscopy, UV/Vis and FTIR spectrophotometry. Curcumin-sulfanilamide compound exhibited the best antibacterial activity against gram-negative bacteria compared to curcumin and the curcumin-derived compound containing isoxazole with inhibitory zone of 11 mm.

scholarly journals Molecular Characterization of Zinc (Zn) Resistant Bacteria in Banger River, Pekalongan, Indonesia

2018 ◽  
Vol 10 (3) ◽  
pp. 622-628
Author(s):  
Fitri Arum Sasi ◽  
Hermin Pancasakti Kusumaningrum ◽  
Anto Budiharjo
Keyword(s):  
Bacterial Species ◽  
Selective Medium ◽  
Resistant Bacteria ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Indigenous Bacteria ◽  
Gram Positive Bacteria ◽  
Sequences Analysis

Indigenous bacteria are able to remove the metals contamination in environment. This study aimed to assess the resistance of bacterial species to Zinc (Zn) in Banger River, Pekalongan City. The bacteria from three different parts of Banger River were isolated and inoculated in Zn-selective medium. Then, molecular identification to determine the bacteria species was conducted using polymerase chain reaction (PCR) by applying forward-reverse 16SrRNA gene primers. The sequences analysis was conducted using MUSCLE and MEGA6. There were seven dominant species that possibly resistant to Zn. Approximately, every isolate could reach more than 95 % from 2000 ppm of Zn in the medium. The higher absorption of Zn was found in Z5 isolate. The seven bacteria species were clustered into nine genera i.e. Klebsiela, Xenorhabdus, Cronobacter, Enterobacter, Escherichia, Shigella and Sporomusa known as Gram Negative bacteria and Clostridium and Bacillus as Gram Positive bacteria. In Gram Positive bacteria, especially Bacillus sp, carboxyl group in peptidoglycan play a role as metal binder. In Gram-negative bacteria, lipopolysaccharide (LPS) which is highly anionic component on the outer membrane, able to catch the Zn. Besides that, Enterobacter activates endogen antioxidants such as glutathione peroxidase (GSHPx), glutathione reductase (GR), catalase (CAT) and superoxide dismutase (SOD). The research found there was possible seven novel indigenous bacteria species in Banger that able to remove Zn from the sediment extremely. This finding can be developed as an eco-friendly approach to reduce metals pollution using local microorganisms.

scholarly journals Campylobacter jejuni Contains Two Fur Homologs: Characterization of Iron-Responsive Regulation of Peroxide Stress Defense Genes by the PerR Repressor

1999 ◽  
Vol 181 (20) ◽  
pp. 6371-6376 ◽  
Author(s):  
Arnoud H. M. van Vliet ◽  
Marie-Louise A. Baillon ◽  
Charles W. Penn ◽  
Julian M. Ketley
Keyword(s):  
Campylobacter Jejuni ◽  
Double Mutant ◽  
Cumene Hydroperoxide ◽  
Iron Level ◽  
Gram Negative Bacteria ◽  
Phenotypic Analysis ◽  
Gram Negative ◽  
Stress Genes ◽  
Peroxide Stress

ABSTRACT Expression of the peroxide stress genes alkyl hydroperoxide reductase (ahpC) and catalase (katA) of the microaerophile Campylobacter jejuni is repressed by iron. Whereas iron repression in gram-negative bacteria is usually carried out by the Fur protein, previous work showed that this is not the case in C. jejuni, as these genes are still iron repressed in aC. jejuni fur mutant. An open reading frame encoding a Fur homolog (designated PerR for “peroxide stress regulator”) was identified in the genome sequence of C. jejuni. TheperR gene was disrupted by a kanamycin resistance cassette in C. jejuni wild-type and fur mutant strains. Subsequent characterization of the C. jejuni perR mutants showed derepressed expression of both AhpC and KatA at a much higher level than that obtained by iron limitation, suggesting that expression of these genes is controlled by other regulatory factors in addition to the iron level. Other iron-regulated proteins were not affected by theperR mutation. The fur perR double mutant showed derepressed expression of known iron-repressed genes. Further phenotypic analysis of the perR mutant, furmutant, and the fur perR double mutant showed that theperR mutation made C. jejuni hyperresistant to peroxide stress caused by hydrogen peroxide and cumene hydroperoxide, a finding consistent with the high levels of KatA and AhpC expression, and showed that these enzymes were functional. Quantitative analysis of KatA expression showed that both the perR mutation and thefur mutation had profound effects on catalase activity, suggesting additional non-iron-dependent regulation of KatA and, by inference, AhpC. The PerR protein is a functional but nonhomologous substitution for the OxyR protein, which regulates peroxide stress genes in other gram-negative bacteria. Regulation of peroxide stress genes by a Fur homolog has recently been described for the gram-positive bacterium Bacillus subtilis. C. jejuni is the first gram-negative bacterium where non-OxyR regulation of peroxide stress genes has been described and characterized.

scholarly journals Preparation characterization and biological activity of some new tetra - azo compounds

2008 ◽  
pp. 35-44
Keyword(s):  
Ph Value ◽  
Chemical Properties ◽  
Azo Compounds ◽  
Gram Negative Bacteria ◽  
Gram Positive Bacteria ◽  
Phenol Derivatives ◽  
Visible Spectra ◽  
Physical And Chemical ◽  
And Chemical Properties

In this paper , preparation and characterization of some tetra azo compounds .Azo coupling of 3`,3,4`,4- tetra amino biphenyl with phenol and some phenol derivatives in alkaline solution gave azo dyes. I.R and U.V. visible spectra were recorded to identify the three azo compounds prepared . Some physical and chemical properties such as molar absorption coefficient in different pH value and maximum absorption λ maxwere investigated. The biological effect of these dye against two gram positive Bacteria (S.aureuse) and other two gram negative Bacteria (P.aeruginosa) is presented .

scholarly journals Synthesis and Characterization of Some New Pyrazoline and Isoxazoline Derivatives as Antibacterial Agents

2016 ◽  
Vol 13 (3) ◽  
pp. 568-577
Author(s):  
Baghdad Science Journal
Keyword(s):  
Sodium Hydroxide ◽  
Antibacterial Agents ◽  
Amine Hydrochloride ◽  
Gram Negative Bacteria ◽  
Gram Positive Bacteria ◽  
In Vitro Antibacterial Activity ◽  
Derivatives Of ◽  
Number Of Bacteria

In this paper some chalcones (C1-C8) are prepared based on the reaction of one mole of substituted acetophenone with one mole of substituted benzaldehydes in the presence of (40%) sodium hydroxide as a base. Pyrazolines (P1–P8) are prepared from the reaction of chalcones (C1-C8) with hydrazine hydrate. Isoxazoline (I1-I8) is prepared from the reaction of chalcones (C1-C8) with hydroxyl amine hydrochloride in the presence of (10%) sodium hydroxide as a base. These compounds are characterized by using various physical and spectral methods. The compounds are screened for their in vitro antibacterial activity using gram-positive bacteria and gram-negative bacteria. Several derivatives of pyrazolines and isoxazolines are produced well to moderate activities against number of bacteria.

scholarly journals Synthesis, Characterization of Biologically Potent Novel Chalcones Bearing Urea, Thiourea and Acetamide Linkages

2014 ◽  
Vol 36 ◽  
pp. 281-294
Author(s):  
Nirali S. Mewada ◽  
Dhruvin R. Shah ◽  
Kishor H. Chikhalia
Keyword(s):  
Antifungal Activity ◽  
Dilution Method ◽  
Gram Negative Bacteria ◽  
Antibacterial And Antifungal Activity ◽  
Gram Positive Bacteria ◽  
H Nmr ◽  
Antibacterial And Antifungal ◽  
Antimicrobial And Antifungal Activities

Three series of some novel chalcone based urea, thiourea and acetamide derivatives were designed, synthesized and screened for their antimicrobial and antifungal activities. All the synthesized compounds are first reported. The structures of the compounds were elucidated with the aid of elemental analysis and spectral methods including IR, 1H-NMR spectral data. The prepared compounds were evaluated for antibacterial activity against two Gram-positive bacteria (Staphylococcus aureus, Staphylococcus pyogenus), two Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli). The title compounds were also investigated for their antifungal activity using the broth micro dilution method. The bioassay results showed that compounds a few compounds showed good to superior in vitro antibacterial and antifungal activity.

scholarly journals SCREENING OF RHAMNOLIPIDS FROM Pseudomonas spp. AND EVALUATION OF ITS ANTIMICROBIAL AND ANTIOXIDANT POTENTIAL

2020 ◽  
Vol 3 (3) ◽  
pp. 46-51
Author(s):  
Ayana Rose Mendoza ◽  
Jenny Marie Patalinghug ◽  
Grace Canonigo ◽  
Jonie Yee
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Agar Plate ◽  
Positive Control ◽  
Gram Negative Bacteria ◽  
Zone Of Inhibition ◽  
Gram Positive Bacteria ◽  
Emulsification Index ◽  
Cave Sediments ◽  
Free Radical Scavenging Assay

Biosurfactants are amphipathic compounds that are useful in industries and are also used in bioremediation. Rhamnolipids (RL) are biosurfactant mostly produced by the genus Pseudomonas. This study screened 6 strains of Pseudomonas isolated from underwater cave sediments to determine if they were capable of producing rhamnolipids. The biosurfactant production of potential strains was screened by Parafilm-M Test, Oil spreading technique, Microplate assay, Emulsification Index, CTAB Agar plate method, Anthrone test, and Thin Layered Chromatography. The study showed that only 3 strains had the potential to produce rhamnolipids, these were Pseudomonas poae, Pseudomonas fluorescens and Pseudomonas libanensis. The antimicrobial activity of the crude rhamnolipid extracts was tested against two Gram-negative bacteria (Escherichia coli, Serratia marcescens) and two Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus) by the conventional minimum  inhibitory concentration (MIC). The antioxidant activity of the crude rhamnolipid extracts was determined through DPPH free radical scavenging assay. All rhamnolipid extracts had a positive correlation between increasing concentrations and the zone of inhibition against test microorganisms. Rhamnolipids from P. libanensis had the lowest MIC among the other extracts, indicating its potency against the test bacteria. The rhamnolipid extracts were effective at inhibiting the test bacteria compared to the positive control, Nitrofurantoin. The antioxidant activity of the crude rhamnolipid extracts was determined through DPPH. Crude rhamnolipid extracts exhibited antioxidant activity but not as great as that of ascorbic acid.

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