Comparison of the activity spectra against pathogens of bacterial strains producing a mutacin or a lantibiotic

2001 ◽  
Vol 47 (4) ◽  
pp. 322-331 ◽  
Author(s):  
Hélène Morency ◽  
Marilaine Mota-Meira ◽  
Gisèle LaPointe ◽  
Christophe Lacroix ◽  
Marc C Lavoie
Keyword(s):  
Drug Resistance ◽  
Campylobacter Jejuni ◽  
Bacterial Pathogens ◽  
The Other ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Major Threat ◽  
Antibiotic Compounds ◽  
Resistant Strains ◽  
Further Development

The increase of drug resistance among bacterial pathogens is currently a major threat in hospital settings. New and more efficient antibiotic compounds have to be developed to fight infectious diseases. In the present work, a deferred antagonism test was used to determine the activity of different bacterial strains producing either a mutacin or a lantibiotic against bacterial pathogens. The mutacins A, B, C, D, I, K, L, M, and nisins A and Z were active against all enterococci tested. Mutacins A and B, and nisins A and Z inhibited all the staphylococci tested. Except for the strains producing mutacins P, Q, and X, all the other producing strains inhibited the streptococci tested. Mutacins A, B, I, J, T, nisins A and Z, and epidermin inhibited the two antibiotic-resistant strains of Neisseria gonorrhoeae tested. Mutacins A, B, C, D, and nisins A and Z inhibited Campylobacter jejuni and Helicobacter pylori. Thus, the wide activity spectra of nisin A and Z are confirmed. These results also indicate that many of the mutacins, especially those of groups A, B, C, D, I, J, K, L, M, and T, could be candidates for further development as useful antibiotics.Key words: mutacin, lantibiotic, bacteriocin, antibiotic.

Transferred drug-resistance in Eimeria maxima

Parasitology ◽  
1975 ◽  
Vol 71 (3) ◽  
pp. 385-392 ◽  
Author(s):  
L. P. Joyner ◽  
C. C. Norton
Keyword(s):  
Drug Resistance ◽  
The Other ◽  
Drug Resistant ◽  
Resistance Factors ◽  
Eimeria Maxima ◽  
Series Of Experiments ◽  
Resistant Strains ◽  
Drug Resistant Strains

A series of experiments is described in which two drug-resistant strains of Eimeria maxima were passaged together in untreated chicks. The resultant oocysts were then inoculated into chicks treated with both drugs. When strains resistant to methyl benzoquate and sulphaquinoxaline or clopidol and sulphaquinoxaline were used the resultant infections were not controlled by the double treatment, indicating the acquisition of resistance factors by one strain from the other. When strains resistant to clopidol and methyl benzoquate were used the phenomenon was not observed.

Lipids of antibiotic-resistant and -susceptible members of the Enterobacteriaceae

1977 ◽  
Vol 23 (8) ◽  
pp. 1045-1051 ◽  
Author(s):  
William J. Suling ◽  
William M. O'Leary
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Analysis ◽  
Lower Amount ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Cyclopropane Fatty Acids ◽  
Resistant Strains ◽  
Lower Ratio ◽  
Layer Chromatography ◽  
Chloroform Methanol

Lipids of antibiotic-resistant and related -susceptible strains of the Enterobacteriaceae were extracted with chloroform–methanol and characterized by thin-layer chromatography, densitometry, and fatty acid analysis using gas chromatography. Quantitative differences which correlated with antibiotic resistance existed among the phospholipids and fatty acids. A relatively higher concentration of a ninhydrin-positive phospholipid concomitant with a lower amount of phosphatidylethanolamine was observed in antibiotic-resistant strains of Serratia marcescens. Bacterial strains which harbored R-factor 222 had a higher ratio of phosphatidylglycerol to diphosphatidylglycerol than their respective parent strains while those strains which were resistant to the polymyxins had a lower ratio of these phospholipids. Differences in the relative amounts of certain unsaturated and cyclopropane fatty acids were observed between susceptible and resistant strains. Such differences, however, were dependent upon a particular genus and species.

scholarly journals Antibacterial Role of SO42− , NO3− , C2O42− and CH3CO2− Anions on Cu(II) and Zn(II) Complexes of a Thiadiazole-derived Pyrrolyl Schiff Base

2002 ◽  
Vol 8 (5) ◽  
pp. 263-267 ◽  
Author(s):  
Zahid H. Chohan ◽  
Humayun Pervez ◽  
Abdul Rauf ◽  
Claudiu T. Supuran
Keyword(s):  
Schiff Base ◽  
Metal Ion ◽  
Condensation Reaction ◽  
Analytical Data ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Novel Approach ◽  
Resistant Strains ◽  
New Compounds

A condensation reaction of 2-amino-1,3,4-thiadiazole with 2-pyrrolecarboxaldehyde to form tridentate NNN donor Schiff base has been performed. The prepared Schiff base was further used for the formation of metal complexes having stoichiometry [M(L)2]Xn , where M=Cu(II) or Zn(II), L=N-(2-pyrrolylmethylene)-2-amino-1,3,4-thiadiazole, X=SO42− , NO3− , C2O42− or CH3CO2− and n=1 or 2. The new compounds described here have been characterized by their physical, spectral and analytical data, and have been screened against several bacterial strains such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The antibacterial potency of the Schiff base increased upon chelation/complexation, having the same metal ion (cation) but different anions opening up a novel approach in finding new ways to fight against antibiotic resistant strains.

scholarly journals Naturally-Occurring Alkaloids of Plant Origin as Potential Antimicrobials against Antibiotic-Resistant Infections

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3619
Author(s):  
Bruno Casciaro ◽  
Laura Mangiardi ◽  
Floriana Cappiello ◽  
Isabella Romeo ◽  
Maria Rosa Loffredo ◽  
...  
Keyword(s):  
Chemical Potential ◽  
Higher Plants ◽  
Antimicrobial Activities ◽  
New Drugs ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Naturally Occurring ◽  
Resistant Strains ◽  
Function Relationship ◽  
Conventional Antibiotics

Antibiotic resistance is now considered a worldwide problem that puts public health at risk. The onset of bacterial strains resistant to conventional antibiotics and the scarcity of new drugs have prompted scientific research to re-evaluate natural products as molecules with high biological and chemical potential. A class of natural compounds of significant importance is represented by alkaloids derived from higher plants. In this review, we have collected data obtained from various research groups on the antimicrobial activities of these alkaloids against conventional antibiotic-resistant strains. In addition, the structure–function relationship was described and commented on, highlighting the high potential of alkaloids as antimicrobials.

scholarly journals Prevalence of drug resistance-conferring mutations associated with isoniazid and rifampicin resistant Mycobacterium tuberculosis in Ethiopia: A systematic review and meta-analysis

2020 ◽  
Author(s):  
Melese Abate Reta ◽  
Birhan Alemnew ◽  
Biruk Beletew Abate
Keyword(s):  
Drug Resistance ◽  
Gene Mutation ◽  
Meta Analysis ◽  
Gene Mutations ◽  
Subsequent Development ◽  
Treatment Regimens ◽  
Pooled Prevalence ◽  
Mdr Tb ◽  
Resistant Strains ◽  
Further Development

AbstractBackgroundDrug resistance tuberculosis (DR-TB) continues to be a major public health threat globally. Due to the development of many rapid molecular diagnostic tools to detect gene mutations in M.tuberculosis (Mtb), specific genes conferring resistance to different anti-TB drugs have been identified. The aim of this meta-analysis was to assess the prevalence of the gene mutations associated with rifampicin (RIF) and isoniazid (INH) resistant Mtb in Ethiopia.MethodsUsing PRISMA guideline, we systematically searched a literature on PubMed/MEDLINE, Web of Science, Scopus electronic databases, Cochrane library, and other database sources. The data analysis was done using STATA 11. The pooled prevalence of the gene mutations associated with resistance to RIF and INH were estimated using the random effect model. Heterogeneity was measured by the I2 statistical test, and the publication bias through the funnel plot and the Egger’s regression test.ResultsAmong all antimycobacterial resistance tested TB patients, prevalence of resistance to any anti-TB drug was 31.3%, while multidrug resistance TB (MDR-TB), any RIF and INH resistance were 22.2%, 24.9%, and 27.9%, respectively. In total, 909 (95.8%) of 949 INH resistant Mtb isolates had detectable gene mutation in katG315 and 5.9% in the inhA gene. The meta-analysis derived an estimated pooled prevalence of katGMUT1(S315T1) in INH resistant Mtb was 89.18% (95%CI 81.94-96.43%), while a pooled inhAMUT1 (C15T) resistant Mtb prevalence was 77.48% (95% CI 57.84-97.13%). Besides, 769 (90.8%) of 847 RIF resistant strains had detectable rpoB gene mutation, commonly in rpoBMUT3(S531L) probe (550 cases). The meta-analysis resulting a pooled rpoBMUT3(S531L) resistant Mtb prevalence of 74.20 % (95%CI 66.39-82.00%).ConclusionsRIF resistant Mtb isolates were spread widely, mainly with S531L mutation. Similarly, INH resistant Mtb isolates were spread with S315T1 and C15T mutations. It is significant to detect S531L among RIF resistant and S315T1 and C15T mutations among INH resistant isolates as it may be a determinant for subsequent development of MDR-TB. Rapid diagnosis of RIF and INH resistant Mtb strains in TB patients would expedite modification of treatment regimens, and proper infection control interventions could be taken on time to reduce the risk of further development and transmission of MDR-TB.HighlightsTuberculosis(TB), particularly drug resistance TB (DR-TB) continues to be a major public health threat globally. Herein, we used a systematic literature search on reliable electronic databases, and perform a meta-analysis to assess the prevalence of the gene mutations associated with rifampicin (RIF) and isoniazid (INH) resistant Mtb in Ethiopia. The meta-analysis derived an estimated pooled prevalence of katGMUT1 (S315T1) in INH resistant Mtb was 89.18% (95%CI 81.94-96.43%), while inhAMUT1(C15T) resistant Mtb prevalence was 77.48% (95% CI 57.84-97.13%). Besides, among 90.8% of RIF resistant strains which had detectable rpoB gene mutation, a pooled S531L resistant Mtb prevalence was 74.20% (95%CI 66.39-82.00%). This review revealed that the RIF resistant Mtb strains were spread widely, mainly with S531L mutation, while the INH resistant Mtb isolates were spread widely with S315T1 and C15T mutations. So, it is significant to detect S531L among RIF resistant and S315T1 and C15T mutations among INH resistant isolates as it may be a determinant for subsequent development of MDR-TB. Rapid diagnosis of RIF and INH resistant Mtb strains in TB patients would expedite alteration of treatment regimens, and proper infection control interventions could be taken on time to reduce the risk of further development and transmission of MDR-TB.

scholarly journals Efficiency of combined action of antimicrobial preparations against poly-resistant strains of conditionally-pathogenic bacteria isolated from wounds of surgery patients

2020 ◽  
Vol 11 (3) ◽  
Author(s):  
T. V. Sklyar ◽  
K. V. Lavrentievа ◽  
O. M. Rudas ◽  
О. V. Bilotserkivska ◽  
N. V. Kurahina ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Disk Diffusion Method ◽  
Antibiotic Resistant ◽  
Simultaneous Application ◽  
Strategic Approach ◽  
Resistant Strains

The strategy of use of combination therapy of antibacterial preparations is being broadly introduced to clinical practice to fight bacterial infections caused by poly-resistant strains of microorganisms. From the wounds of surgery patients, we isolated 67 clinical strains of conditionally-pathogenic bacteria identified as Staphylococcus aureus, S. epidermidis, Escherichia coli, Klebsiella pneumoniaе, Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa. Using disk diffusion method, the isolated bacterial strains were found to be most resistant to penicillin preparations: ampicillin, oxacillin, amoxicillin/clavulanat; tetracycline and cephalosporin of the II generation – cefoxitin. The percentage of strains insusceptible to these antibacterial preparations accounted for 65.0%. The division of antibiotic-resistant cultures regarding phenotype groups according to the level of their antibiotic resistance allowed determination of 4 PDR-, 8 XDR- and 14 MDR-strains. During the studies on experimental determining of MIC of antibiotic and antiseptics in the condition of applying them as monopreparations against isolated bacterial cultures, we saw significant exceess in the threshold values of MIC, and, first of all, regarding pandrug-resistant and extensive drug-resistant clinical microbial isolates. Use of combinations of antibacterial preparations was found to show the synergic effect of antibiotics (ceftriaxone, ofloxacin, gentamicin) and antiseptics (chlorhexidine, decasan), which is expressed in simultaneous decrease in MIC of each of the tested preparations by 2–8 times compared with their isolative application. Such combinatory approach regarding simultaneous application of antibacterial preparations may be considered as one of the most promising ways to combat poly-resistant clinical isolates of conditionally-pathogenic microorganisms and to offer a new strategic approach to prevention of spread of antibiotic resistance as a phenomenon in medical practice.

Sign in / Sign up

Export Citation Format

Share Document