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1.
Anim Microbiome ; 5(1): 44, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715236

RESUMO

Endosymbionts are known to have significant effects on their insect hosts, including nutrition, reproduction, and immunity. Insects gut microbiota is a critical component that affects their physiological and behavioral characteristics. The black cutworm (BCW), Agrotis ipsilon, is an economically important lepidopteran pest that has a diverse gut microbiome composed of nine species belonging to three phyla: Proteobacteria, Actinobacteria, and Firmicutes. This study was conducted to investigate the diversity of gut bacteria isolated from BCW larvae and moths and their effects on metabolism and pesticide degradation. The bacterial isolates were identified using the 16 S rRNA gene. The study showed that the gut microbiome composition significantly affected the metabolism of BCW larvae. Based on the screening results of synthesis of digestive enzymes and pesticide degradation, Brachybacterium conglomeratum and Glutamicibacter sp were selected to perform the remaining experiments as single isolates and consortium. The consortium-fed larvae showed high metabolic indices compared to antibiotic-fed larvae and the control. The gut bacteria were also shown to degrade three pesticide groups. Concerns regarding the health risk of chlorpyrifos have been raised due to its extensive use in agriculture. The isolated B. conglomeratum was more effective in chlorpyrifos degradation than the consortium. Furthermore, the study also examined the presence of sex related endosymbionts (Wolbachia, Spiroplasma, and Rickettsia) in the reproductive tissues of adults. The outcomes demonstrated that none of the examined endosymbionts existed. In conclusion, the study highlights the importance of the gut microbiome in insect physiology and behavior and its potential applications in biotechnology. It provides insights into developing eco-friendly pest control and bioremediation strategies using gut bacteria.

2.
Microorganisms ; 11(5)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37317117

RESUMO

Multidrug-resistant microorganisms have become a significant public health threat, and traditional antibiotics are becoming ineffective. Photodynamic therapy (PDT) is a promising alternative that utilizes photosensitizers and light to produce Reactive Oxygen Species (ROS) that can kill microorganisms. Zinc phthalocyanine (ZnPc) is a promising photosensitizer due to its strong affinity for encapsulation in nanoemulsions and its antimicrobial properties. In this study, nanoemulsion was prepared using Miglyol 812N, a surfactant, and distilled water to dissolve hydrophobic drugs such as ZnPc. The nanoemulsion was characterized by its particle size, polydispersity index, Transmission Electron Microscope and Zeta potential, and the results showed that it was an efficient nanocarrier system that facilitated the solubilization of hydrophobic drugs in water. The use of ZnPc encapsulated in the nanoemulsion produced through the spontaneous emulsification method resulted in a significant reduction in cell survival percentages of gram-positive Staphylococcus aureus and gram-negative Escherichia coli by 85% and 75%, respectively. This may be attributed to the more complex cell membrane structure of E. coli compared to S. aureus. This demonstrates the potential of nanoemulsion-based PDT as an effective alternative to traditional antibiotics for treating multidrug-resistant microorganisms.

3.
Microorganisms ; 11(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37374947

RESUMO

The accumulation of xenobiotic compounds in different environments interrupts the natural ecosystem and induces high toxicity in non-target organisms. Diclofenac is one of the commonly used pharmaceutical drugs that persist in the environment due to its low natural degradation rate and high toxicity. Therefore, this study aimed to isolate potential diclofenac-degrading bacteria, detect the intermediate metabolites formed, and determine the enzyme involved in the degradation process. Four bacterial isolates were selected based on their ability to utilize a high concentration of diclofenac (40 mg/L) as the sole carbon source. The growth conditions for diclofenac degradation were optimized, and bacteria were identified as Pseudomonas aeruginosa (S1), Alcaligenes aquatilis (S2), Achromobacter spanius (S11), and Achromobacter piechaudii (S18). The highest percentage of degradation was recorded (97.79 ± 0.84) after six days of incubation for A. spanius S11, as analyzed by HPLC. To detect and identify biodegradation metabolites, the GC-MS technique was conducted for the most efficient bacterial strains. In all tested isolates, the initial hydroxylation of diclofenac was detected. The cleavage step of the NH bridge between the aromatic rings and the subsequent cleavage of the ring adjacent to or in between the two hydroxyl groups of polyhydroxylated derivatives might be a key step that enables the complete biodegradation of diclofenac by A. piechaudii S18, as well as P. aeruginosa S1. Additionally, the laccase, peroxidase, and dioxygenase enzyme activities of the two Achromobacter strains, as well as P. aeruginosa S1, were tested in the presence and absence of diclofenac. The obtained results from this work are expected to be a useful reference for the development of effective detoxification bioprocesses utilizing bacterial cells as biocatalysts. The complete removal of pharmaceuticals from polluted water will stimulate water reuse, meeting the growing worldwide demand for clean and safe freshwater.

4.
Molecules ; 27(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35458737

RESUMO

Fungal-bacterial co-culturing is a potential technique for the production of secondary metabolites with antibacterial activity. Twenty-nine fungal species were screened in a co-culture with carbapenem-resistant Klebsiella pneumoniae at different temperatures. A temperature of 37 ° showed inhibition of bacterial growth. Antimicrobial susceptibility testing for K. pneumoniae was conducted to compare antibiotic resistance patterns before and after the co-culture. Genotypic comparison of the K. pneumonia was performed using next generation sequencing (NGS). It was shown that two out of five K. pneumoniae, with sequence type ST 101 isolates, lost bla-OXA48, bla-CTX-M-14, tir, strA and strB genes after the co-culture with Scopulariopsis brevicaulis fungus. The other three isolates (ST 383 and 147) were inhibited in the co-culture but did not show any changes in resistance. The total ethyl acetate extract of the fungal-bacterial co-culture was tested against K. pneumoniae using a disc diffusion method. The concentration of the crude extract was 0.97 mg/µL which resulted in total inhibition of the bacteria. Using chromatographic techniques, the purified compounds were identified as 11-octadecenoic acid, 2,4-Di-tert-butylphenol, 2,3-Butanediol and 9-octadecenamide. These were tested against K. pneumoniae using the well diffusion method at a concentration of 85 µg/µL which resulted in total inhibition of bacteria. The co-culture results indicated that bacteria under chemical stress showed variable responses and induced fungal secondary metabolites with antibacterial activities.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Klebsiella , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/metabolismo , Testes de Sensibilidade Microbiana , beta-Lactamases/metabolismo
5.
ACS Pharmacol Transl Sci ; 5(3): 177-178, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35295932

RESUMO

The SARS-CoV-2 pandemic has caused the death of 5.5 million people and the infection of more than 323 million people as of January 2022. The remarkable increase in pathogenicity and virulence might have occurred as a result of viral RNA mutations. To date, few antiviral drugs have been authorized for emergency use, but not yet approved, to treat mild to moderate COVID-19, with serious drawbacks and side effects. Antimicrobial peptides (AMPs) play an important role in the host's innate and adaptive immune system against a wide range of microbial infections. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is thought to be used to increase the recombinant biosynthesis of AMPs. There have been studies that reported the production of AMPs using CRISPR. Therefore, CRISPR is expected to play an important role in the production of AMPs as next-generation, safe, affordable, and efficient antiviral drugs in general and for the treatment of COVID-19 in particular, in addition to AMPs being efficient immunomodulators.

6.
Biology (Basel) ; 12(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36671720

RESUMO

The peach fruit fly, Bactrocera zonata (Tephritidae), is economically relevant as a highly polyphagous pest infesting over 50 host plants including commercial fruit and horticultural crops. As an invasive species, B. zonata was firmly established in Egypt and holds potential to spread further across the Mediterranean basin. The present study demonstrated that the peach fruit fly was found multiplying in olive orchards at two distant locations in Egypt. This is the first report of B. zonata developing in olives. COI barcoding has revealed evidence for high diversity across these peach fruit fly populations. These data are consistent with multiple rather than a single event leading to both peach fruit fly invasion to Egypt and its adaptation to olive. Comparative microbiomics data for B. zonata developing on different host plants were indicative for microbiome dynamics being involved in the adaptation to olive as a new niche with a potential adaptive role for Erwinia or Providencia bacteria. The possibility of symbiont transfer from the olive fruit fly to the peach fruit fly is discussed. Potentially host switch relevant bacterial symbionts might be preferred targets of symbiosis disruption strategies for integrated pest management or biological control of B. zonata.

7.
Biomolecules ; 11(10)2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34680148

RESUMO

Cyclic dipeptides, also know as diketopiperazines (DKP), the simplest cyclic forms of peptides widespread in nature, are unsurpassed in their structural and bio-functional diversity. DKPs, especially those containing proline, due to their unique features such as, inter alia, extra-rigid conformation, high resistance to enzyme degradation, increased cell permeability, and expandable ability to bind a diverse of targets with better affinity, have emerged in the last years as biologically pre-validated platforms for the drug discovery. Recent advances have revealed their enormous potential in the development of next-generation theranostics, smart delivery systems, and biomaterials. Here, we present an updated review on the biological and structural profile of these appealing biomolecules, with a particular emphasis on those with anticancer properties, since cancers are the main cause of death all over the world. Additionally, we provide a consideration on supramolecular structuring and synthons, based on the proline-based DKP privileged scaffold, for inspiration in the design of compound libraries in search of ideal ligands, innovative self-assembled nanomaterials, and bio-functional architectures.


Assuntos
Dicetopiperazinas/química , Dipeptídeos/química , Neoplasias/tratamento farmacológico , Prolina/química , Dicetopiperazinas/uso terapêutico , Dipeptídeos/genética , Dipeptídeos/uso terapêutico , Descoberta de Drogas , Humanos , Neoplasias/genética , Peptídeos Cíclicos/química , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/uso terapêutico , Prolina/genética , Prolina/uso terapêutico
8.
Acta Parasitol ; 66(2): 593-604, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33389546

RESUMO

PURPOSE: The study of the Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier), as an invasive pest of palm trees. METHODS: In this study, 36 RPW individuals were collected from 6 different locations in Egypt. The presences of endosymbionts in the RPW individuals were assayed. The phylogenetic analysis of the RPW inhabiting Egypt was conducted using Cytochrome c oxidase sub-unit 1 (CO1) gene. RESULTS: Spiroplasma was found, for the first time, in all individuals, while Rickettsia was found, for the first time, in individuals collected from only 3 of the 6 locations. Endosymbionts harbouring Egyptian RPW were closely related to those harbouring Diptera and\or Trombidiformes associated with palm trees. This may be due to horizontal transmission through palm sap or through ectoparasites living on the RPW. Finally, the phylogenetic analysis of the RPW inhabiting Egypt was conducted. The collected individuals were closely related to Saudi Arabia specimens collected from the eastern region. Thus, Saudi Arabia may be the origin of the RPW which invaded Egypt. Individuals from populations inhabiting the same geographical locations were closely related. This may be due to secondary invasion incidents that may have taken place through transportation of infested date palm trees and offshoots from infected to uninfected locations. CONCLUSION: This study reports the first incidence for the presence and coexistence of Spiroplasma and Rickettsia in RPW collected from Egypt. In addition, it was found that the collected individuals of RPW were closely related to a Saudi haplotype. Thus, Saudi Arabia may be the origin of infection which invaded Egypt.


Assuntos
Besouros , Rickettsia , Spiroplasma , Gorgulhos , Animais , Egito , Humanos , Filogenia , Rickettsia/genética
9.
Molecules ; 26(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467522

RESUMO

Peptides are fragments of proteins that carry out biological functions. They act as signaling entities via all domains of life and interfere with protein-protein interactions, which are indispensable in bio-processes. Short peptides include fundamental molecular information for a prelude to the symphony of life. They have aroused considerable interest due to their unique features and great promise in innovative bio-therapies. This work focusing on the current state-of-the-art short peptide-based therapeutical developments is the first global review written by researchers from all continents, as a celebration of 100 years of peptide therapeutics since the commencement of insulin therapy in the 1920s. Peptide "drugs" initially played only the role of hormone analogs to balance disorders. Nowadays, they achieve numerous biomedical tasks, can cross membranes, or reach intracellular targets. The role of peptides in bio-processes can hardly be mimicked by other chemical substances. The article is divided into independent sections, which are related to either the progress in short peptide-based theranostics or the problems posing challenge to bio-medicine. In particular, the SWOT analysis of short peptides, their relevance in therapies of diverse diseases, improvements in (bio)synthesis platforms, advanced nano-supramolecular technologies, aptamers, altered peptide ligands and in silico methodologies to overcome peptide limitations, modern smart bio-functional materials, vaccines, and drug/gene-targeted delivery systems are discussed.


Assuntos
Anti-Infecciosos/farmacologia , Antivirais/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Aminoácidos/química , Anti-Infecciosos/química , Antivirais/química , Simulação por Computador , Cosmecêuticos/química , Cosmecêuticos/uso terapêutico , Suplementos Nutricionais , Técnicas de Transferência de Genes , Humanos , Lactoferrina/química , Bicamadas Lipídicas , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Peptídeos/administração & dosagem , Células-Tronco , Vacinas de Subunidades Antigênicas/química , Vacinas de Subunidades Antigênicas/farmacologia , Tratamento Farmacológico da COVID-19
10.
ACS Pharmacol Transl Sci ; 3(4): 780-782, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32821884

RESUMO

COVID-19 is currently considered as a life-threatening pandemic viral infection. Finding an antiviral drug or a vaccine is the only route for humans' survival against it. To date, no specific antiviral treatment has been confirmed. Antimicrobial peptides (AMPs) have been widely regarded as a promising solution to combat harmful microorganisms. They are biologically active molecules produced by different organisms as an essential component of their innate immune response against invading pathogens. Lactoferrin (LF), one of the AMPs, is an iron-binding glycoprotein that is present in several mucosal secretions. The antiviral activity of LF exists against a wide range of human and animal viruses (DNA and RNA). LF was proven to increase the host immunity against viral infection. Since LF is one of the constituents of breast milk and significantly located at the mucosal layers of the human body, it is considered the first line of defense against microbial infection. LF was reported to have antiviral activity against SARS-CoV infection. The significant antiviral activity of LF makes it a potential option as an immunity enhancer, a drug or a drug conjugate with conventional antivirals. The affordability, environmental safety, and efficiency of LFs will make them superior to all other control strategies.

11.
Photodiagnosis Photodyn Ther ; 30: 101677, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32006650

RESUMO

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease. There is no standard treatment modality for OLP. Recently, photodynamic therapy (PDT) has been advocated as a new treatment modality for OLP. AIM: The aim of the present study is to compare the effect of PDT using methylene blue (MB) as a photosensitizer to the effect of topical corticosteroids in the treatment of erosive OLP lesions. MATERIALS AND METHODS: Our study included 20 patients with erosive OLP. Patients were divided into two groups. The study group included 10 patents which received MB-PDT. Patients were instructed to use MB as mouth path for 5 min. After 10 min, we applied focal red light on OLP lesions (wavelength 660 nm, Intensity 100-130 m W/cm2) for 2 min. The PDT was applied twice a week for four weeks. In the control group, 10 patients were instructed to apply topical betamethasone valerate ointment 100 mg on OLP lesion three times per day for four weeks. Subjective, objective scores and lesion size were recorded at time zero, after 2 weeks and after 4 weeks from the start of treatments. RESULTS: Both groups showed statistically significant differences between time zero and the 4th week of treatment in subjective, objective scores and the area of the lesions. MB-PDT showed a higher degree of improvement than topical corticosteroids between time zero and the 4th week of treatment. CONCLUSION: Photodynamic therapy can be used as a treatment for erosive OLP. PDT offers improvement of OLP subjective and objective scores without major side effects.


Assuntos
Líquen Plano Bucal , Fotoquimioterapia , Doença Crônica , Humanos , Líquen Plano Bucal/tratamento farmacológico , Azul de Metileno/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico
13.
Arab J Gastroenterol ; 20(2): 74-80, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30905635

RESUMO

BACKGROUND AND STUDY AIMS: Diarrhoea and urinary tract infection (UTI) are common clinical problems. Meanwhile, Escherichia coli (E. coli), is the commonest bacterial pathogen reported in both of them. This study aimed to evaluate the pathogenic E. coli (PEC) in stool of acute diarrhoea and urine of UTI regarding their virulence genes and their influence on the susceptibility to routinely prescribed antibiotics. PATIENTS AND METHODS: Twenty two stool and another 22 urine samples of patients with acute diarrhoea and UTI respectively were collected from patients admitted at Kasr Al-Ainy Hospital, Faculty of Medicine, Cairo University, Egypt. E. coli isolation, identification of their phyla; chuA, yjaA, and TspE4.C2, and further identification of 10 virulent genes; fimH, papC, papG//, papG///, papEF, afa, sfa, CNF1, iroN & hlyA was performed. Antibiotic susceptibility was studied against quinolones, gentamicin (GM), and trimethoprim-sulphamethoxazole (TMP-SMX). RESULTS: The studied virulence genes were comparably detected in both pathogenic samples. In diarrheogenic E. coli (DEC); phylum A was significantly related to both ciprofloxacin (CIP) and TMP-SMX resistance, and both of the virulence genes fimH and iroN were significantly related to all the studied antibiotics resistance, while afa was significantly related to nalidixic acid (NA) resistance. In uropathogenic E. coli (UEC); phylum D was significantly related to CIP and levofloxacin resistance, and both of the virulence genes fimH and iroN were significantly related to most of the studied antibiotics resistance. CONCLUSION: The isolated PEC was evidently and broadly resistant to the studied antibiotics, with limited influence of their phyla and virulence genes (fimH and iroN).


Assuntos
Antibacterianos/farmacologia , Diarreia/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Infecções Urinárias/microbiologia , Doença Aguda , Egito , Escherichia coli/classificação , Escherichia coli/genética , Fezes/microbiologia , Gentamicinas/farmacologia , Humanos , Quinolonas/farmacologia , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Virulência/genética
14.
Infect Drug Resist ; 11: 2211-2217, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519059

RESUMO

INTRODUCTION: Serratia marcescens is a significant hospital-acquired pathogen, and many outbreaks of S. marcescens infection have been reported in neonates. We report a sudden breakout of S. marcescens harboring the bla IMP-4 and bla VIM-2 metallo-ß-lactamase (MBL) genes that occurred from March to August 2015 in the neonatal intensive care unit of Cairo University Hospital, Cairo, Egypt. METHODS: During the study period, 40 nonduplicate clinical isolates of S. marcescens were collected from blood culture samples. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to identify each isolate. Then, minimum inhibitory concentrations of different antibiotics were assessed by the Vitek 2 compact system. Screening of the MBL genes bla IMP, bla VIM, bla SIM-1, bla SPM-1, and bla GIM-1 as well as the carbapenemase genes KPC, NDM, OXA-48, SME-1, and SME-2 were evaluated. Pulsed field gel electrophoresis was preformed to detect the genetic relationship of the isolates. RESULTS: Analysis showed that 37.5% of the S. marcescens clinical isolates were resistant to meropenem (minimum inhibitory concentrations ≥ 2 µg/mL), and bla IMP-4 and bla VIM-2 were the most prevalent MBL genes (42.5% and 37.5%, respectively). None of the other investigated genes were observed. Pulsed field gel electrophoresis typing revealed two discrete clones; 33/40 (82.5%) were pulsotype A and 7/40 (17.5%) were pulsotype B. CONCLUSION: Here, we report for the first time the detection of MBL-producing S. marcescens isolates, particularly IMP-4 and VIM-2 recovered from inpatients with bacteremias from the intensive care unit at Cairo University Hospital.

15.
J Egypt Public Health Assoc ; 91(2): 73-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27455084

RESUMO

BACKGROUND: The increasing incidence of hospital-acquired infections due to extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae represent a major health problem because of few therapeutic alternatives. The fecal flora can represent a reservoir for ESBL genes. Integrons are genetic structures capable of capturing gene cassettes that usually encode antibiotic-resistance determinants. OBJECTIVES: To investigate the antimicrobial susceptibility of fecal isolates of ESBL-producing Escherichia coli and Klebsiella pneumoniae from hospitalized and nonhospitalized Egyptian patients and to determine the prevalence of class 1 and class 2 integrons together with the most common ESBL-producing genes (bla TEM, SHV, CTX-M, and OXA) among the collected isolates. MATERIALS AND METHODS: Ninety-six fecal samples were collected: 48 samples from hospitalized patients admitted at Kasr Al-Ainy University Hospital, Cairo and 48 from outpatient clinics. Samples were inoculated on MacConkey agar and identified. All isolates were tested for their susceptibility to different antimicrobial agents using a standard disk diffusion method. The double-disk synergy test was applied for screening ESBL. All ESBL-producing isolates were confirmed by molecular testing to detect ESBL-encoding genes (SHV, TEM, CTX-M, and OXA). To identify the strains carrying integrons 1 and 2, the conserved regions of integron-encoded integrase gene intI1 and intI2 were amplified. RESULTS: E. coli isolates accounted for 52.1% of the isolates collected from hospitalized patients and 60.4% of those collected from outpatient clinics. Results of the double-disk synergy test were positive in all E. coli and K. pneumoniae isolates, indicating the presence of ESBL production. Isolates of both groups showed variably high degrees of resistance to ciprofloxacin and co-trimoxazole. The most predominant ESBL gene in both groups was the bla CTX-M gene (93.8%) and the least prevalent was the bla OXA gene, which was not detected in any of the study isolates. Between the other two genes, the bla TEM gene was more common than the bla SHV gene in the two study groups. Class 1 integron was more prevalent among hospitalized patients, being detected in 64.6% of isolates from this group. Class 1 integron was linked with the bla CTX-M gene (P=0.039). Class 2 integron was more prevalent in the nonhospitalized group (85.4%) compared with the hospitalized group (50%) (P<0.001). CONCLUSION AND RECOMMENDATIONS: ESBL-producing E. coli and K. pneumoniae showed a marked degree of antibiotic resistance in both hospitalized and nonhospitalized study groups. The high prevalence of class 1 and 2 integrons among isolates of both groups has a serious impact on the spread of antibiotic resistance.


Assuntos
Infecção Hospitalar/genética , Farmacorresistência Bacteriana , Escherichia coli/genética , Fezes/microbiologia , Integrons , beta-Lactamases/genética , Egito , Feminino , Humanos , Masculino , Polimorfismo de Fragmento de Restrição , Manejo de Espécimes , Resistência beta-Lactâmica
16.
Insect Sci ; 21(6): 699-706, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24124002

RESUMO

Male-killing is 1 of 4 known strategies that inherited parasitic endosymbionts have evolved to manipulate their host's reproduction. In early male-killing, infected male offspring are killed early in embryogenesis. Within the Insecta, male-killing bacteria have been found in a wide range of hosts. The Coccinellidae families of beetles, better known as ladybirds, are particularly prone to male-killer invasion. In samples of the coccinellid, Coccinula crotchi, from Japan, a new male-killing bacterium was revealed by phenotypic assay. Molecular genetic analysis revealed the identity to be a tetracycline-sensitive Flavobacterium that causes female-biased offspring sex ratio. Furthermore, that Flavobacterium strain was found to be closely related to the Flavobacterium causing male-killing in the congeneric Japanese coccinellid, Coccinula sinensis, which was collected from the same region. However, we found slightly different Flavobacterium strains infecting C. sinensis from regions with different environmental conditions. This may be an indication of horizontal transmission of male-killing Flavobacterium between these 2 ladybird spices. Finally, environmental conditions may affect the spread of male-killing bacteria among their hosts.


Assuntos
Besouros/microbiologia , Flavobacterium/classificação , Flavobacterium/genética , Animais , Besouros/fisiologia , DNA Bacteriano/genética , Meio Ambiente , Feminino , Flavobacterium/fisiologia , Japão , Masculino , Filogenia , Razão de Masculinidade , Tetraciclina/farmacologia
17.
PLoS One ; 8(1): e54218, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349831

RESUMO

Ladybirds are a hot-spot for the invasion of male-killing bacteria. These maternally inherited endosymbionts cause the death of male host embryos, to the benefit of female sibling hosts and the bacteria that they contain. Previous studies have shown that high temperatures can eradicate male-killers from ladybirds, leaving the host free from infection. Here we report the discovery of two maternally inherited sex ratio distorters in populations of a coccinellid, Coccinella undecimpunctata, from a hot lowland region of the Middle East. DNA sequence analysis indicates that the male killing is the result of infection by Wolbachia, that the trait is tetracycline sensitive, and that two distinct strains of Wolbachia co-occur within one beetle population. We discuss the implications of these findings for theories of male-killing and suggest avenues for future field-work on this system.


Assuntos
Clima , Besouros/microbiologia , Temperatura Alta , Wolbachia/fisiologia , Animais , Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Besouros/efeitos dos fármacos , Egito , Feminino , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Jordânia , Masculino , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Fatores Sexuais , Razão de Masculinidade , Especificidade da Espécie , Tetraciclina/farmacologia , Wolbachia/classificação , Wolbachia/genética
18.
Eur J Med Chem ; 46(11): 5636-40, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22000920

RESUMO

A series of trifluoromethyl-substituted hexahydropyrimidine derivatives were efficiently synthesized in excellent yields via one-pot three-component reaction of aromatic aldehydes, ethyl trifluoroacetoacetate and thiourea(urea) in presence of p-toluenesulfonic acid under solvent-free conditions at room temperature by grinding. The present method does not involve any hazardous organic solvent and has proven to be simple, efficient, environmentally benign and cost-effective compared with the classical synthetic methods. These compounds were screened for their antibacterial activities against Escherichia coli and Bacillus thuringiensis and found to exhibit remarkably better antibacterial activities than the control drug.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Técnicas de Química Sintética/métodos , Química Verde/métodos , Pirimidinas/síntese química , Pirimidinas/farmacologia , Anti-Infecciosos/química , Bacillus thuringiensis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Pirimidinas/química
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