1
|
Decker T, Rautenbach M, Khan S, Khan W. Antibacterial efficacy and membrane mechanism of action of the Serratia-derived non-ionic lipopeptide, serrawettin W2-FL10. Microbiol Spectr 2024; 12:e0295223. [PMID: 38842361 PMCID: PMC11218446 DOI: 10.1128/spectrum.02952-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 05/14/2024] [Indexed: 06/07/2024] Open
Abstract
The study aimed to investigate the antibacterial activity, cytotoxicity, and mechanism of action of the non-ionic, cyclic lipopeptide, serrawettin W2-FL10 against Staphylococcus aureus. W2-FL10 exhibited potent activity against the Gram-positive bacteria S. aureus, Enterococcus faecalis, Enterococcus faecium, Listeria monocytogenes, and Bacillus subtilis, with minimum inhibitory concentration (MIC) values ranging from 6.3 to 31.3 μg/mL, while no activity was observed against Gram-negative bacteria. Broth microdilution assays showed that W2-FL10 interacted with key cell membrane components, such as lipid phosphatidyl glycerol and lipoteichoic acid of S. aureus. Upon membrane interaction, W2-FL10 dissipated membrane potential within 12 min and increased S. aureus membrane permeability within 28-40 min, albeit at slower rates and higher concentrations than the lytic peptide melittin. The observed membrane permeability, as detected with propidium iodide (PI), may be attributed to transmembrane pores/lesions, possibly dependent on dimer-driven lipopeptide oligomerization in the membrane. Scanning electron microscopy (SEM) imaging also visually confirmed the formation of lesions in the cell wall of one of the S. aureus strains, and cell damage within 1 h of exposure to W2-FL10, corroborating the rapid time-kill kinetics of the S. aureus strains. This bactericidal action against the S. aureus strains corresponded to membrane permeabilization by W2-FL10, indicating that self-promoted uptake into the cytosol may be part of the mode of action. Finally, this lipopeptide exhibited low to moderate cytotoxicity to the Chinese hamster ovarian (CHO) cell line in comparison to the control (emetine) with an optimal lipophilicity range (log D value of 2.5), signifying its potential as an antibiotic candidate. IMPORTANCE Antimicrobial resistance is a major public health concern, urgently requiring antibacterial compounds exhibiting low adverse health effects. In this study, a novel antibacterial lipopeptide analog is described, serrawettin W2-FL10 (derived from Serratia marcescens), with potent activity displayed against Staphylococcus aureus. Mechanistic studies revealed that W2-FL10 targets the cell membrane of S. aureus, causing depolarization and permeabilization because of transmembrane lesions/pores, resulting in the leakage of intracellular components, possible cytosolic uptake of W2-FL10, and ultimately cell death. This study provides the first insight into the mode of action of a non-ionic lipopeptide. The low to moderate cytotoxicity of W2-FL10 also highlights its application as a promising therapeutic agent for the treatment of bacterial infections.
Collapse
Affiliation(s)
- Tanya Decker
- Water Health Research Centre, Faculty of Health Sciences, University of Johannesburg, Doornfontein, Johannesburg, Gauteng, South Africa
| | - Marina Rautenbach
- BioPep Peptide Group, Department of Biochemistry, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| | - Sehaam Khan
- Water Health Research Centre, Faculty of Health Sciences, University of Johannesburg, Doornfontein, Johannesburg, Gauteng, South Africa
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa
| |
Collapse
|
2
|
Laka K, Mbita Z. P53-Related Anticancer Activities of Drimia calcarata Bulb Extracts Against Lung Cancer. Front Mol Biosci 2022; 9:876213. [PMID: 35769912 PMCID: PMC9235921 DOI: 10.3389/fmolb.2022.876213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/02/2022] [Indexed: 01/18/2023] Open
Abstract
Current lung cancer treatment strategies are ineffective, and lung cancer cases continue to soar; thus, novel anticancer drugs and targets are needed, and medicinal plants are promising to offer better alternatives. This study was aimed at analysing two p53 splice variants during the potential anticancer activities of Drimia calcarata (Dc) methanol and water extracts against different human lung cancer cell lines of varying p53 mutation status, and these included mutant H1573 and mutant H1437 and p53-wild type (A549) cells. The anticancer activities of the Dc extracts were assessed by establishing the cytotoxic effect and the apoptosis-inducing capacity of these extracts, using the MTT assay and Annexin V analysis, respectively, with the latter confirmed using fluorescence microscopy. The molecular mechanisms induced by these extracts were further evaluated using cell cycle analysis and RT-PCR. Both extracts demonstrated safety against noncancerous lung MRC-5 fibroblasts and exhibited significant anticancer potency (p < 0.001) against the H1437 (IC50 values: 62.50 μg/ml methanol extract and 125 μg/ml WE), H1573 (IC50 value: 125 μg/ml for both extracts) and A549 (IC50 value: 500 μg/ml ME). The water extract had no effect on the viability of A549 cells. Treated H1437 cells underwent p53-dependent apoptosis and S-phase cell cycle arrest while H1573 treated cells underwent p53-independed apoptosis and G0/G1 cell cycle arrest through upregulation of p21 mRNA expression levels. The expression levels of STAT1, STAT3, STAT5A and STAT5B genes increased significantly (p < 0.001) following the treatment of H1573 cells with ME and WE. Treatment of H1437 cells with ME upregulated the STAT1, STAT3, STAT5A and STAT5B mRNAs. Our results indicate that the proliferative inhibitory effect of D. calcarata extracts on A549 and H1573 cells is correlated with the suppression of Bcl-2, STAT3 and STAT5B while that is not the case in H1437 cells. Thus, our results suggest that the dysregulation of anti-apoptotic molecules Bcl-2, STAT3, STAT5A and STAT5B in H1437 may play a role in cancer cell survival, which may consequently contribute to the development of p53-mutated non-small human lung cancer. Our results indicate that D. calcarata is a promising source of anticancer agents for the treatment of p53-mutant human non-small lung cancer cells than the p53-wild type human non-small lung cancer cells.
Collapse
|
3
|
Kemboi D, Langat MK, Siwe-Noundou X, Krause RWM, Isaacs ML, Tembu VJ. In vitro antibacterial and cytotoxic effects of Euphorbia grandicornis Blanc chemical constituents. BMC Complement Med Ther 2022; 22:90. [PMID: 35337309 PMCID: PMC8957186 DOI: 10.1186/s12906-022-03571-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/14/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Euphorbia grandicornis is widely utilized in traditional medicine for the treatment of microbial infections including sexually transmitted diseases such as syphilis, gonorrhoea and for healing of wounds. OBJECTIVE The aim of this work was to isolate and evaluate the antibacterial and anticancer activities of Euphorbia grandicornis chemical constituents. METHODS Chemical constituents were isolated and identified using various spectroscopic techniques such as IR, MS, and NMR. The single point growth inhibitory potential of the compounds was determined using a 96-well plate based assay. RESULTS The CH2Cl2 crude extracts exhibited potent antibacterial activity against Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538 with percentage growth of 94.90 ± 4.24 and 29.47 ± 4.89 respectively. Hence, the CH2Cl2 crude extract was further subjected to column chromatography which resulted in the isolation of methyl 2,5-dihydroxybenzoate (1), n-octyl benzoate (2), friedelanol (3), and germanicol (4) and identification of compounds 12-24 for the first time in the species based on the LC-MS/MS spectroscopic data. The purified compounds (1-4), and previously reported compounds (5-11) were evaluated for antibacterial activities against S. aureus and E. coli, as well as the cytotoxicity effects against HeLa cells. Of the purified compounds, methyl 2,5-dihydroxybenzoate (1), was the most active against E.coli and S. aureus with a percentage growth of 19.12 ± 0.65 and 23.32 ± 0.23 respectively. β-amyrin (6), and β-sitosterol (8), were active against S. aureus with percentage growth of 27.17 ± 0.07, and 47.79 ± 2.99 respectively. CONCLUSION The results obtained from this study indicate that E. grandicornis, is a rich source of chemical constituents that may provide new lead compounds for the development of antibacterial agents.
Collapse
Affiliation(s)
- Douglas Kemboi
- Department of Chemistry, Tshwane University of Technology, Pretoria, 0001, South Africa. .,Department of Chemistry, Rhodes University, Makhanda (Grahamstown), 6140, South Africa.
| | - Moses K Langat
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey, TW9 3AE, UK
| | - Xavier Siwe-Noundou
- Pharmaceutical Sciences Department, School of Pharmacy, Sefako Makgatho Health Sciences University, Pretoria, 0204, South Africa
| | - Rui W M Krause
- Department of Chemistry, Rhodes University, Makhanda (Grahamstown), 6140, South Africa
| | - Michelle Louise Isaacs
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda (Grahamstown),, 6140, South Africa
| | | |
Collapse
|
4
|
Suleman Z, Engwa GA, Shauli M, Musarurwa HT, Katuruza NA, Sewani-Rusike CR. Neuroprotective effects of Lippia javanica (Burm.F.) Spreng. Herbal tea infusion on Lead-induced oxidative brain damage in Wistar rats. BMC Complement Med Ther 2022; 22:4. [PMID: 34983490 PMCID: PMC8725456 DOI: 10.1186/s12906-021-03471-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/30/2021] [Indexed: 12/25/2022] Open
Abstract
Background Though Lippia javanica (Burm.f.) Spreng antioxidant activity has been demonstrated, its effect in protecting the brain from lead (Pb)-induced oxidative damage is unknown. This study investigated the effect of L. javanica against Pb-induced oxidative stress, inflammation, apoptosis and acetylcholinesterase activity in rat’s brain. Methods L. javanica herbal tea infusion was prepared, its phytochemical constituent was revealed by liquid chromatography-Mass spectrometer (LC-MS) and was administered simultaneously with Pb. Four groups of male Wistar rats (n = 5/group) were used: control received distilled water; Pb-acetate group received 50 mg Pb/ Kg bodyweight (bw), treatment group received 50 mg Pb/ Kg Pb-acetate + 5 ml/kg bw L. javanica and L. javanica group received 5 ml/Kg bw of L. javanica tea infusion only. After 6 weeks of treatment, oxidative status, acetylcholinesterase activity, inflammation and apoptosis was assessed in brain tissue which was also histologically examined. Results Mean brain and heart weight was reduced (p < 0.05) while liver and spleen weights were increased (p < 0.05) in Pb exposed animals but were prevented by L. juvanica treatment. Treatment with L. javanica increased (p < 0.05) overall brain antioxidant status (glutathione and superoxide dismutase activities) and reduced lipid peroxidation (p < 0.05) compared to the Pb exposed animals. Pro-inflammatory cytokine tumour necrotic factor-alpha, pro-apoptosis Bax protein and anticholinesterase activity were reduced (p < 0.05) in Pb-L. javanica treated animals compared to the Pb exposed group. Histological examination confirmed neuroprotective effects of L. javanica as evidenced by reduced apoptosis/necrosis and inflammation-induced vacuolization and oedema in the hippocampus. The L. javanica treatment alone had no detrimental effects to the rats. LC-MS analysis revealed L. javanica to be rich in phenolics. Conclusions This study demonstrated that L. javanica, rich in phenolics was effective in reducing Pb-induced brain oxidative stress, inflammation, apoptosis, acetylcholinesterase activity and neuronal damage.
Collapse
Affiliation(s)
- Zubair Suleman
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Godwill A Engwa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Mathulo Shauli
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Hannibal T Musarurwa
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Ndinashe A Katuruza
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Constance R Sewani-Rusike
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa.
| |
Collapse
|
5
|
Mokwena MAM, Engwa GA, Nkeh-Chungag BN, Sewani-Rusike CR. Athrixia phylicoides tea infusion (bushman tea) improves adipokine balance, glucose homeostasis and lipid parameters in a diet-induced metabolic syndrome rat model. BMC Complement Med Ther 2021; 21:292. [PMID: 34844584 PMCID: PMC8628465 DOI: 10.1186/s12906-021-03459-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/03/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Central obesity and insulin resistance are associated with metabolic syndrome (MetS) which is aggravated by diet and sedentary lifestyle. Athrixia phylicoides (AP) is reported by rural communities to have medicinal benefits associated with MetS such as obesity and type 2 diabetes. This study was aimed to investigate the effects of AP on diet-induced MetS in Wistar rats to validate its ethnopharmacological use. METHODS AP was profiled for phytochemicals by LC-MS. After induction of MetS with high energy diet (HED), 30 male rats were divided into five treatment groups (n = 6): normal diet control, HED control, HED + AP 50 mg/Kg BW, HED + AP 100 mg/Kg BW and HED + 50 mg/Kg BW metformin. The rats were treated daily for 8 weeks orally after which weight gain, visceral fat, total cholesterol, free fatty acids (FFAs) and adipokine regulation; leptin: adiponectin ratio (LAR) were assessed. Also, glucose homeostatic parameters including fasting blood glucose (FBG), oral glucose tolerance test (OGTT), glucose transporter 4 (GLUT 4), insulin and homeostatic model assessment of insulin resistance (HOMA-IR) were determined. RESULTS Findings showed that AP was rich in polyphenols. The HED control group showed derangements of the selected blood parameters of MetS. AP reversed diet-induced weight gain by reducing visceral fat, total blood cholesterol and circulating FFAs (p ≤ 0.05). Treatment with AP improved adipokine regulation depicted by reduced LAR (p<0.05). Treatment with AP improved parameters of glucose homeostasis as demonstrated by reduced FBG and HOMA-IR (p ≤ 0.05) and increased GLUT 4 (p<0.05). CONCLUSION Athrixia phylicoides tea infusion was shown to possess anti-obesity and anti-inflammatory properties, improved glucose uptake and reduce insulin resistance in diet-induced MetS in rats which could be attributed to its richness in polyphenols. Therefore, AP could have potential benefits against type 2 diabetes and obesity which are components of MetS validating its ethnopharmacological use.
Collapse
Affiliation(s)
- Madigoahle A M Mokwena
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Godwill Azeh Engwa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Benedicta N Nkeh-Chungag
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa
| | - Constance R Sewani-Rusike
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, Mthatha, 5117, South Africa.
| |
Collapse
|
6
|
Mfengu MOM, Shauli M, Engwa GA, Musarurwa HT, Sewani-Rusike CR. Lippia javanica (Zumbani) herbal tea infusion attenuates allergic airway inflammation via inhibition of Th2 cell activation and suppression of oxidative stress. BMC Complement Med Ther 2021; 21:192. [PMID: 34225706 PMCID: PMC8256649 DOI: 10.1186/s12906-021-03361-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 06/16/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lippia javanica (lemon bush) is commonly used in the treatment of respiratory ailments, including asthma in southern African countries but there is no scientific evidence to support this claim. This study investigated the anti-inflammatory, antioxidant and anti-asthmatic effects of L. javanica using a rat model of asthma. METHODS A 5% w/v L. javanica tea infusion was prepared and characterised by liquid chromatography-mass spectrometer (LC-MS). Animals were intraperitoneally sensitized with ovalbumin (OVA) and subsequently challenged intranasal with OVA on day 15 except the control group. Animals were grouped (n = 5/group) for treatment: unsensitised control, sensitised control, sensitised + prednisolone and sensitised + L. javanica at 50 mg/kg/day and 100 mg/kg/day - equivalent to 1 and 2 cups of tea per day, respectively. After 2 weeks of treatment, bronchoalveolar lavage fluid (BALF) was collected for total and differential white blood cell (WBC) count. Nitric oxide (NO), lipid peroxidation and antioxidants were also assessed in BALF. Ovalbumin specific IgE antibody and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-alpha were measured in serum. Lung and muscle tissues were histological examined. RESULTS L. javanica was rich in phenolic compounds. OVA sensitisation resulted in development of allergic asthma in rats. L. javanica treatment resulted in a reduction in total WBC count as well as eosinophils, lymphocytes and neutrophils in BALF. L. javanica inhibited Th2-mediated immune response, which was evident by a decrease in serum IgE and inflammatory cytokines: IL-4, IL-5, IL-13 and TNF-α. L. javanica treatment also reduced malondialdehyde (MDA) and NO, and increased superoxide dismutase, glutathione and total antioxidant capacity. Histology showed significant attenuation of lung infiltration of inflammatory cells, alveolar thickening, and bronchiole smooth muscle thickening. CONCLUSION L. javanica suppressed allergic airway inflammation by reducing Th2-mediated immune response and oxidative stress in OVA-sensitized rats which may be attributed to the presence of phenolic compound in the plant. This finding validates the traditional use of L. javanica in the treatment of respiratory disorders.
Collapse
Affiliation(s)
- Mvuyisi O M Mfengu
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117, Mthatha, South Africa
| | - Mathulo Shauli
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117, Mthatha, South Africa
| | - Godwill A Engwa
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, Walter Sisulu University PBX1, 5117, Mthatha, South Africa
| | - Hannibal T Musarurwa
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117, Mthatha, South Africa
| | - Constance R Sewani-Rusike
- Department of Human Biology, Faculty of Health Sciences, Walter Sisulu University PBX1, 5117, Mthatha, South Africa.
| |
Collapse
|
7
|
Laka K, Mapheto K, Mbita Z. Selective in vitro cytotoxicity effect of Drimia calcarata bulb extracts against p53 mutant HT-29 and p53 wild-type Caco-2 colorectal cancer cells through STAT5B regulation. Toxicol Rep 2021; 8:1265-1279. [PMID: 34195018 PMCID: PMC8233163 DOI: 10.1016/j.toxrep.2021.06.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 06/04/2021] [Accepted: 06/14/2021] [Indexed: 12/14/2022] Open
Abstract
Colorectal cancer is the fourth leading cause of oncological-related deaths and the third most diagnosed malignancy, worldwide. The emergence of chemoresistance is a fundamental drawback of colorectal cancer therapies and there is an urgent need for novel plant-derived therapeutics. In this regard, other compounds are needed to improve the efficacy of treatment against colorectal cancer. Medicinal plants have been effectively used by traditional doctors for decades to treat various ailments with little to no side effects. Drimia calcarata (D. calcarata) is one of the plants used by Pedi people in South Africa to treat a plethora of ailments. However, the anticancer therapeutic use of D. calcarata is less understood. Thus, this study was aimed at evaluating the potential anticancer activities of D. calcarata extracts against human colorectal cancer cells. The phytochemical analysis and antioxidant activity were analysed using LC-MS, DPPH, and FRAP. The inhibitory effects and IC50 values of D. calcarata extracts were determined using the MTT assay. Induction of cellular apoptosis was assessed using fluorescence microscopy, the Muse® Cell Analyser, and gene expression analysis by Polymerase Chain Reaction (PCR). Water extract (WE) demonstrated high phenolic, tannin, and flavonoid contents than the methanol extract (ME). LC-MS data demonstrated strong differences between the ME and WE. Moreover, WE showed the best antioxidant activity than ME. The MTT data showed that both ME and WE had no significant activity against human embryonic kidney Hek 293 cell line that served as non-cancer control cells. Caco-2 cells demonstrated high sensitivity to the ME and demonstrated resistance toward the WE, while HT-29 cells exhibited sensitivity to both D. calcarata extracts. The expression of apoptosis regulatory genes assessed by PCR revealed an upregulation of p53 by ME, accompanied by downregulation of Bcl-2 and high expression of Bax after treatment with curcumin. The Bax gene was undetected in HT-29 cells. The methanol extract induced mitochondrial-mediated apoptosis in colorectal Caco-2 and HT-29 cells and WE induced the extrinsic apoptotic pathway in HT-29 cells. ME downregulated STAT1, 3, and 5B in HT-29 cells. The D. calcarata bulb extracts, therefore, contain potential anticancer agents that can be further targeted for cancer therapeutics.
Collapse
Affiliation(s)
- K. Laka
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovenga, 0727, Polokwane, South Africa
| | - K.B.F. Mapheto
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovenga, 0727, Polokwane, South Africa
| | - Z. Mbita
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovenga, 0727, Polokwane, South Africa
| |
Collapse
|
8
|
Rautenbach M, Kumar V, Vosloo JA, Masoudi Y, van Wyk RJ, Stander MA. Oligomerisation of tryptocidine C, a Trp-rich cyclodecapeptide from the antimicrobial tyrothricin complex. Biochimie 2020; 181:123-133. [PMID: 33333170 DOI: 10.1016/j.biochi.2020.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/17/2020] [Accepted: 12/12/2020] [Indexed: 01/07/2023]
Abstract
Tryptocidine C (TpcC, cyclo[D-Phe1-Pro2-Trp3-D-Trp4-Asn5-Gln6-Trp7-Val8-Orn9-Leu10]) is a broad-spectrum antimicrobial peptide in the tyrothricin complex produced by a soil bacterium, Brevibacillus parabrevis. Electrospray mass spectrometric studies reveal the oligomerisation of TpcC into dimers and higher oligomers, analogous to tyrocidine C (TrcC, Trp7 replaced by Tyr7). Ion mobility mass spectrometry (IMMS) further confirms the formation of stable peptide dimers and tetramers with diameters of 2.7 nm and 3.3 nm, respectively, calculated from collisional cross section (CCS). Molecular dynamic simulations and docking studies support the formation of amphipathic dimers, with a diameter of 2.5 ± 0.07 nm calculated from low energy model CCS. Circular dichroism and IMMS studies point towards dynamic hydrogen-bonded conformational changes up to 28-33 μM after which the structures become more static (or in equilibrium). Fluorescence studies indicate aromatic stacking of Trp residues with a CMC of 18 μM in aqueous solutions. The concentration and time dependent interaction of Trp in oligomers indicate cooperativity in the TpcC oligomerisation that leads to the formation of higher order microscopic structures. Scanning electron microscopy studies unequivocally shows that TpcC forms nanospheres with a mean diameter of 25 nm. Repeated smaller oligomeric units, possibly dimers and tetramers, self-assemble to form these nanospheres.
Collapse
Affiliation(s)
- Marina Rautenbach
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa.
| | - Vikas Kumar
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa.
| | - J Arnold Vosloo
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | - Yasamin Masoudi
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | - Rosalind J van Wyk
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | - Marietjie A Stander
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa; LC-MS Unit of the Central Analytical Facility, Stellenbosch University, Stellenbosch, South Africa
| |
Collapse
|
9
|
Zhang R, Fan X, Jiang X, Zou M, Xiao H, Wu G. Multiple Mechanisms of the Synthesized Antimicrobial Peptide TS against Gram-Negative Bacteria for High Efficacy Antibacterial Action In Vivo. Molecules 2020; 26:molecules26010060. [PMID: 33374458 PMCID: PMC7795306 DOI: 10.3390/molecules26010060] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 12/02/2022] Open
Abstract
The emergence of drug-resistant bacteria emphasizes the urgent need for novel antibiotics. The antimicrobial peptide TS shows extensive antibacterial activity in vitro and in vivo, especially in gram-negative bacteria; however, its antibacterial mechanism is unclear. Here, we find that TS without hemolytic activity disrupts the integrity of the outer bacterial cell membrane by displacing divalent cations and competitively binding lipopolysaccharides. In addition, the antimicrobial peptide TS can inhibit and kill E. coli by disintegrating the bacteria from within by interacting with bacterial DNA. Thus, antimicrobial peptide TS’s multiple antibacterial mechanisms may not easily induce bacterial resistance, suggesting use as an antibacterial drug to be for combating bacterial infections in the future.
Collapse
Affiliation(s)
- Rui Zhang
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
| | - Xiaobo Fan
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
| | - Xinglu Jiang
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
| | - Mingyuan Zou
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
| | - Han Xiao
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
| | - Guoqiu Wu
- Medical School, Southeast University, Nanjing 210009, China; (R.Z.); (X.F.); (X.J.); (M.Z.); (H.X.)
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Southeast University, Nanjing 210009, China
- Department of Clinical Laboratory Medicine, Zhongda Hospital, Southeast University, Nanjing 210009, China
- Correspondence: ; Tel.: +86-25-83272503
| |
Collapse
|
10
|
López-Prieto A, Rodríguez-López L, Rincón-Fontán M, Cruz JM, Moldes AB. Characterization of extracellular and cell bound biosurfactants produced by Aneurinibacillus aneurinilyticus isolated from commercial corn steep liquor. Microbiol Res 2020; 242:126614. [PMID: 33045681 DOI: 10.1016/j.micres.2020.126614] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/14/2020] [Accepted: 09/28/2020] [Indexed: 12/19/2022]
Abstract
The presence of biosurfactants produced by a Bacillus strain in corn steep liquor (CSL), a wastewater stream of the corn milling process, has been recently discovered. However, the species responsible for their production has not been identified at the moment. Therefore, in this work, the Bacillus strain isolated from CSL, with capacity to produce biosurfactants, was subjected to amplification and sequence analysis of the 16S rRNA, being identified as Aneurinibacillus aneurinilyticus. This strain has been proved to be endospore forming and thermophile, what would explain its presence in the commercial CSL. It was observed that the strain under evaluation has the ability to produce both cell-bound and extracellular biosurfactant extracts, which were characterized in this work. The electrospray ionization mass spectrometry (ESI) analysis of the biosurfactant extracts revealed that the extracellular biosurfactant produced by Aneurinibacillus aneurinilyticus is composed by a mixture of lipopeptides, containing C16 and C18 fatty acids and amino acids, including valine, phenylalanine, proline, cysteine, histidine, aspartic acid/asparagine, alanine, glycine, leucine/isoleucine, with biomarkers between 1025-458 m/z. Conversely, the cell-bound biosurfactant extract produced by Aneurinibacillus aneurinilyticus was composed by the cyclic decapeptide gramicidin S, with a characteristic peak at 571 m/z, and lipopeptides with characteristic peaks between 1034-705 m/z, containing alanine, glycine, cysteine, serine, proline, aspartic acid/asparagine, similarly to the amino acid sequence of the extracellular biosurfactant extract.
Collapse
Affiliation(s)
- Alejandro López-Prieto
- Chemical Engineering Department, School of Industrial Engineering - Centro de Investigación Tecnológico Industrial (MTI), University of Vigo, Campus As Lagoas-Marcosende, 36310, Spain
| | - Lorena Rodríguez-López
- Chemical Engineering Department, School of Industrial Engineering - Centro de Investigación Tecnológico Industrial (MTI), University of Vigo, Campus As Lagoas-Marcosende, 36310, Spain
| | - Myriam Rincón-Fontán
- Chemical Engineering Department, School of Industrial Engineering - Centro de Investigación Tecnológico Industrial (MTI), University of Vigo, Campus As Lagoas-Marcosende, 36310, Spain
| | - José Manuel Cruz
- Chemical Engineering Department, School of Industrial Engineering - Centro de Investigación Tecnológico Industrial (MTI), University of Vigo, Campus As Lagoas-Marcosende, 36310, Spain
| | - Ana Belén Moldes
- Chemical Engineering Department, School of Industrial Engineering - Centro de Investigación Tecnológico Industrial (MTI), University of Vigo, Campus As Lagoas-Marcosende, 36310, Spain.
| |
Collapse
|
11
|
Masike K, de Villiers A, Hoffman EW, Brand DJ, Causon T, Stander MA. Detailed Phenolic Characterization of Protea Pure and Hybrid Cultivars by Liquid Chromatography-Ion Mobility-High Resolution Mass Spectrometry (LC-IM-HR-MS). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:485-502. [PMID: 31805232 DOI: 10.1021/acs.jafc.9b06361] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study we report a detailed investigation of the polyphenol composition of Protea pure (P. cynaroides and P. neriifolia) and hybrid cultivars (Black beauty and Limelight). Aqueous methanol extracts of leaf and bract tissues were analyzed by ultrahigh pressure liquid chromatography hyphenated to photodiode array and ion mobility-high resolution mass spectrometric (UHPLC-PDA-IM-HR-MS) detection. A total of 67 metabolites were characterized based on their relative reversed phase (RP) retention, UV-vis spectra, low and high collision energy HR-MS data, and collisional cross section (CCS) values. These metabolites included 41 phenolic acid esters and 25 flavonoid derivatives, including 5 anthocyanins. In addition, an undescribed hydroxycinnamic acid-polygalatol ester, caffeoyl-O-polygalatol (1,5-anhydro-[6-O-caffeoyl]-sorbitol(glucitol)) was isolated and characterized by 1D and 2D NMR for the first time. This compound and its isomer are shown to be potential chemo-taxonomic markers.
Collapse
Affiliation(s)
- Keabetswe Masike
- Department of Biochemistry , Stellenbosch University , Private Bag X1, Matieland , 7602 Stellenbosch , South Africa
| | - André de Villiers
- Department of Chemistry and Polymer Science , Stellenbosch University , Private Bag X1, Matieland , 7602 Stellenbosch , South Africa
| | - Eleanor W Hoffman
- Department of Horticultural Science , Stellenbosch University , Private Bag X1, Matieland , 7602 Stellenbosch , South Africa
| | - D Jacobus Brand
- Department of Chemistry, Central Analytical Facility (NMR Unit) , Stellenbosch University , Matieland, 7602 Stellenbosch , South Africa
| | - Tim Causon
- University of Natural Resources and Life Sciences (BOKU) , Department of Chemistry, Institute of Analytical Chemistry , 1180 Vienna , Austria
| | - Maria A Stander
- Department of Biochemistry , Stellenbosch University , Private Bag X1, Matieland , 7602 Stellenbosch , South Africa
- Central Analytical Facility , Stellenbosch University , Private Bag X1, Matieland , 7602 Stellenbosch , South Africa
| |
Collapse
|
12
|
Dreyer J, Rautenbach M, Booysen E, van Staden AD, Deane SM, Dicks LMT. Xenorhabdus khoisanae SB10 produces Lys-rich PAX lipopeptides and a Xenocoumacin in its antimicrobial complex. BMC Microbiol 2019; 19:132. [PMID: 31195965 PMCID: PMC6567599 DOI: 10.1186/s12866-019-1503-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 05/31/2019] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Xenorhabdus spp. live in close symbiosis with nematodes of the Steinernema genus. Steinernema nematodes infect an insect larva and release their symbionts into the haemocoel of the insect. Once released into the haemocoel, the bacteria produce bioactive compounds to create a semi-exclusive environment by inhibiting the growth of bacteria, yeasts and molds. The antimicrobial compounds thus far identified are xenocoumacins, xenortides, xenorhabdins, indole derivatives, xenoamicins, bicornutin and a number of antimicrobial peptides. The latter may be linear peptides such as the bacteriocins xenocin and xenorhabdicin, rhabdopeptides and cabanillasin, or cyclic, such as PAX lipopeptides, taxlllaids, xenobactin and szentiamide. Thus far, production of antimicrobial compounds have been reported for Xenorhabdus nematophila, Xenorhabdus budapestensis, Xenorhabdus cabanillasii, Xenorhabdus kozodoii, Xenorhabdus szentirmaii, Xenorhabdus doucetiae, Xenorhabdus mauleonii, Xenorhabdus indica and Xenorhabdus bovienii. Here we describe, for the first time, PAX lipopeptides and xenocoumacin 2 produced by Xenorhabdus khoisanae. These compounds were identified using ultraperformance liquid chromatography, linked to high resolution electrospray ionisation mass spectrometry and tandem mass spectrometry. RESULTS Cell-free supernatants of X. khoisanae SB10 were heat stable and active against Bacillus subtilis subsp. subtilis, Escherichia coli and Candida albicans. Five lysine-rich lipopeptides from the PAX group were identified in HPLC fractions, with PAX1' and PAX7 present in the highest concentrations. Three novel PAX7 peptides with putative enoyl modifications and two linear analogues of PAX1' were also detected. A small antibiotic compound, yellow in colour and λmax of 314 nm, was recovered from the HPLC fractions and identified as xenocoumacin 2. The PAX lipopeptides and xenocoumacin 2 correlated with the genes and gene clusters in the genome of X. khoisanae SB10. CONCLUSION With UPLC-MS and MSe analyses of compounds in the antimicrobial complex of X. khoisanae SB10, a number of PAX peptides and a xenocoumacin were identified. The combination of pure PAX1' peptide with xenocoumacin 2 resulted in high antimicrobial activity. Many of the fractions did, however, contain labile compounds and some fractions were difficult to resolve. It is thus possible that strain SB10 may produce more antimicrobial compounds than reported here, as suggested by the APE Ec biosynthetic complex. Further research is required to develop these broad-spectrum antimicrobial compounds into drugs that may be used in the fight against microbial infections.
Collapse
Affiliation(s)
- J Dreyer
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - M Rautenbach
- BIOPEP Peptide Group, Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa.
| | - E Booysen
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - A D van Staden
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - S M Deane
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - L M T Dicks
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa.
| |
Collapse
|
13
|
Li M, Wei Z, Wang J, Jousset A, Friman VP, Xu Y, Shen Q, Pommier T. Facilitation promotes invasions in plant-associated microbial communities. Ecol Lett 2018; 22:149-158. [PMID: 30460736 DOI: 10.1111/ele.13177] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/12/2018] [Accepted: 10/08/2018] [Indexed: 12/31/2022]
Abstract
While several studies have established a positive correlation between community diversity and invasion resistance, it is less clear how species interactions within resident communities shape this process. Here, we experimentally tested how antagonistic and facilitative pairwise interactions within resident model microbial communities predict invasion by the plant-pathogenic bacterium Ralstonia solanacearum. We found that facilitative resident community interactions promoted and antagonistic interactions suppressed invasions both in the lab and in the tomato plant rhizosphere. Crucially, pairwise interactions reliably explained observed invasion outcomes also in multispecies communities, and mechanistically, this was linked to direct inhibition of the invader by antagonistic communities (antibiosis), and to a lesser degree by resource competition between members of the resident community and the invader. Together, our findings suggest that the type and strength of pairwise interactions can reliably predict the outcome of invasions in more complex multispecies communities.
Collapse
Affiliation(s)
- Mei Li
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China
| | - Zhong Wei
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China
| | - Jianing Wang
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China
| | - Alexandre Jousset
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China.,Institute for Environmental Biology, Ecology& Biodiversity, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Ville-Petri Friman
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China.,Department of Biology, University of York, Wentworth Way, YO10 5DD, York, UK
| | - Yangchun Xu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China
| | - Qirong Shen
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, National Engineering Research Center for Organic-based Fertilizers, Nanjing Agricultural University, 210095, Nanjing, China
| | - Thomas Pommier
- Ecologie Microbienne, UMR1418, French National Institute for Agricultural Research (INRA), University Lyon I, F-69622, Villeurbanne, France
| |
Collapse
|
14
|
Stander MA, Van Wyk BE, Taylor MJC, Long HS. Analysis of Phenolic Compounds in Rooibos Tea (Aspalathus linearis) with a Comparison of Flavonoid-Based Compounds in Natural Populations of Plants from Different Regions. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:10270-10281. [PMID: 29063755 DOI: 10.1021/acs.jafc.7b03942] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Tea samples from 17 populations of "wild tea" ecotypes Aspalathus linearis (rooibos tea) and 2 populations of Aspalathus pendula were analyzed. Recent advances in column technology together with high-resolution mass spectrometry were applied to improve resolution, facilitating the identification of several new compounds as well as grouping of the wild tea ecotypes according to their chemical composition. The collisional cross-section data obtained from ion mobility-mass spectrometry is reported for the flavonoids in rooibos for the first time. Enzyme pathways for the synthesis of the unique flavonoids found in rooibos tea are also proposed. A. linearis and A. pendula produce similar combinations of main phenolic compounds, with no diagnostically different discontinuities between populations or species. Northern resprouters (Gifberg and Nieuwoudtville) contain higher phenylpropenoic acid glucoside levels while teas from Wupperthal and surrounding areas were found to contain unique dihydrochalcones (phloridzin and a sieboldin analog), which are reported here for the first time.
Collapse
Affiliation(s)
| | - Ben-Erik Van Wyk
- Department of Botany and Plant Biotechnology, University of Johannesburg , P.O. Box 524, Auckland Park, Johannesburg, 2006 South Africa
| | | | - Helen S Long
- Department of Botany and Plant Biotechnology, University of Johannesburg , P.O. Box 524, Auckland Park, Johannesburg, 2006 South Africa
| |
Collapse
|