scholarly journals The Synthesis and Evaluation of Amidoximes as Cytotoxic Agents on Model Bacterial E. coli Strains

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7577
Author(s):  
Jan Samsonowicz-Górski ◽  
Paweł Kowalczyk ◽  
Dominik Koszelewski ◽  
Anna Brodzka ◽  
Mateusz Szymczak ◽  
...  
Keyword(s):  
Biological Activity ◽  
Organic Synthesis ◽  
Free Amino ◽  
Antibacterial Agents ◽  
Cytotoxic Agents ◽  
Biological Research ◽  
Amino Group ◽  
Hospital Infections ◽  
Bacterial Dna ◽  
E Coli

The biological research on newly synthesized amidoximes, Boc-protected amidoximes and Boc-derived amidines, obtained by a reduction of the parent amidoximes is reported, herein. Due to the presence of a free amino group in both amidines and amidoximes, these compounds can undergo various chemical reactions such as N-alkylation and N-acylation. One such reaction is Boc-protection, often used in organic synthesis to protect the amino and imino groups. Until now, Boc-protected amidoximes have not been tested for biological activity. Amidoxime derivatives were tested on bacterial E. coli strains. Initial cellular studies tests and digestion with Fpg after the modification of bacterial DNA, suggest that these compounds may have greater potential as antibacterial agents compared to antibiotics such as ciprofloxacin (ci), bleomycin (b) and cloxacillin (cl). The described compounds are highly specific for pathogenic E. coli strains on the basis of the model strains used and may be used in the future as new substitutes for commonly used antibiotics in clinical and hospital infections in the pandemic era.

scholarly journals IMMUNOLOGIC PRODUCTION OF ANTIANGIOTENSIN

1960 ◽  
Vol 111 (3) ◽  
pp. 419-427 ◽  
Author(s):  
Sharad D. Deodhar
Keyword(s):  
Biological Activity ◽  
Angiotensin Ii ◽  
Aromatic Amines ◽  
Free Amino ◽  
Parent Compound ◽  
The Other ◽  
Amino Group ◽  
Angiotensin I ◽  
Absolute Requirement ◽  
Specific Activities

Angiotensin II was coupled with bovine γ-globulin (BGG) through the following series of reactions. See PDF for Structure By determinations of the aromatic amine and tyrosine contents of p-aminobenzoylangiotensin II, the number of p-aminobenzoyl residues introduced per molecule of angiotensin II was calculated. Absorption spectra (between 250 and 500 mµ) of BGG complexes of p-aminobenzoylangiotensin II and six different para substituted aromatic amines were compared. Specific activities (dog units/millimicromole) of the different intermediate products were determined. Presence of a terminal, free amino group does not appear to be an absolute requirement for the biological activity of angiotensin II, since substitution of a p-aminobenzoyl radical in this group yields a product with 40 to 50 per cent of the activity of the parent compound. Angiotensin I, on the other hand, is completely inactivated under identical circumstances. Possible implication of this finding has been discussed.

scholarly journals δ-Lactones—A New Class of Compounds That Are Toxic to E. coli K12 and R2–R4 Strains

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2956
Author(s):  
Paweł Kowalczyk ◽  
Barbara Gawdzik ◽  
Damian Trzepizur ◽  
Mateusz Szymczak ◽  
Grzegorz Skiba ◽  
...  
Keyword(s):  
Biological Activity ◽  
Pathogenic Bacteria ◽  
Bacterial Resistance ◽  
Biologically Active ◽  
Toxic Activity ◽  
Bacterial Dna ◽  
E Coli ◽  
New Class ◽  
Anti Cancer ◽  
Taste And Smell

Lactones are among the well-known organic substances with a specific taste and smell. They are characterized by antibacterial, antiviral, anti-inflammatory, and anti-cancer properties. In recent years, among this group of compounds, new biologically active substances have been searched by modifying the main (leading) structure with new analogs with stronger or different responses that may have a toxic effect on the cells of pathogenic bacteria and constitute an alternative to commonly used antibiotics. A preliminary study of δ-lactone derivatives as new potential candidates for antibacterial drugs was conducted. Particular emphasis was placed on the selection of the structure of lactones with the highest biological activity, especially those with fluorine in their structure as a substituent in terms of action on bacterial lipopolysaccharide (LPS) in the model strains of Escherichia coli K12 (without LPS in its structure) and R2–R4 (LPS of different lengths in its structure). In the presented studies, on the basis of the conducted MIC and MBC tests, it was shown that the antibacterial (toxic) activity of lactones depends on their structure and the length of the bacterial LPS in the membrane of specific strains. Moreover, oxidative damage of bacterial DNA isolated from bacteria after modification with newly synthesized compounds after application of the repair enzyme Fpg glycosylase was analyzed. The analyzed damage values were compared with the modification with appropriate antibiotics: ciprofloxacin, bleomycin, and cloxacillin. The presented research clearly shows that lactone derivatives can be potential candidates as substitutes for drugs, e.g., the analyzed antibiotics. Their chemical and biological activity is related to coumarin derivatives and the corresponding δ-lactone groups in the structure of the substituent. The observed results are of particular importance in the case of increasing bacterial resistance to various drugs and antibiotics, especially in nosocomial infections and neoplasms, and in the era of a microbial pandemic.

scholarly journals Antibacterial Activity of Semi Purified Extract of Marine-Derived Trichoderma reesei PDSP 5.7 Using Bioguided Fractionation Method

2020 ◽  
Vol 9 (1) ◽  
pp. 45-54
Author(s):  
Mada Triandala Sibero ◽  
Nunung Febriany Sitepu ◽  
Tao Zhou ◽  
Yasuhiro Igarashi
Keyword(s):  
Antibacterial Activity ◽  
Biological Activity ◽  
Trichoderma Reesei ◽  
Crude Extract ◽  
Antibacterial Agents ◽  
Ethyl Acetate Extract ◽  
Inhibition Zone ◽  
E Coli ◽  
Mycelial Extract ◽  
Fractionation Method

Bioguided fractionation method is commonly used to obtained targeted fraction with certain biological activity. In this study, bioguided fractionation method using HPLC was applied to obtained antibacterial fractions from marine-derived fungus Trichoderma reesei PDSP 5.7. The result shows that fraction from mycelium and medium extract had antibacterial activity against ESBL E. coli and S. enterica ser. Typhi with a range of inhibition zone was 1.35±0.15 to 8.82±0.22 mm2. From 32 fractions of each extract, the mycelial extract had 7 active fractions, 3 active fractions from broth medium which extracted using 1-butanol and 5 active fractions from ethyl acetate extract. This study indicated that crude extract of fungus T. reesei PDSP 5.7 was more potential as the source of antibacterial agents rather than the crude extract that obtained from its broth medium.

scholarly journals The acetylation of insulin

1971 ◽  
Vol 121 (5) ◽  
pp. 737-745 ◽  
Author(s):  
D. G. Lindsay ◽  
S. Shall
Keyword(s):  
Biological Activity ◽  
Free Amino ◽  
Tertiary Structure ◽  
Group Analysis ◽  
Insulin Antibodies ◽  
The Other ◽  
Amino Group ◽  
Amino Groups ◽  
Chloromethyl Ketone ◽  
End Group

The acetylation of the free amino groups of insulin was studied by reaction of the hormone with N-hydroxysuccinimide acetate at pH6.9 and 8.5. The products formed were separated by chromatography on DEAE-Sephadex and were characterized by isoelectric focusing, by end-group analysis, by the incorporation of [3H]acetyl groups in the molecule, and by treatment with trypsin that had been treated with 1-chloro-4-phenyl-3-toluene-p-sulphonamidobutan-2-one (‘tosylphenylalanyl chloromethyl ketone’). Three monosubstituted products, two disubstituted products and one trisubstituted derivative were prepared. The α-amino groups of the terminal residues and the ∈-amino group of the lysine-B29 were the sites of reaction. Acetylation of any of the free amino groups did not affect the biological activity of insulin. It was demonstrated, however, that substitution at the glycine-A1 amino group by the larger residues, acetoacetyl or thiazolidinecarbonyl, produced a decrease in biological activity. Modification of the lysine-B29 or phenylalanine-B1 amino groups with these larger reagents did not affect the biological activity. Modification of the phenylalanine-B1 amino group by any of the three substituents resulted in a large decrease in the affinity of insulin for anti-insulin antibodies raised in the guinea pig. Modification of the other two amino groups did not affect the reaction with antibody. These observations are correlated with the tertiary structure of insulin.

scholarly journals 1,2-Diarylethanols—A New Class of Compounds That Are Toxic to E. coli K12, R2–R4 Strains

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1025
Author(s):  
Paweł Kowalczyk ◽  
Damian Trzepizur ◽  
Mateusz Szymczak ◽  
Grzegorz Skiba ◽  
Karol Kramkowski ◽  
...  
Keyword(s):  
Biological Activity ◽  
Bacterial Resistance ◽  
Inhibitory Concentration ◽  
Initial Study ◽  
New Drugs ◽  
Bacterial Dna ◽  
E Coli ◽  
New Class ◽  
Chemical Groups ◽  
Selection Of

An initial study of 1,2-diarylethanols derivatives as new potential antibacterial drugs candidates was conducted. Particular emphasis was placed on the selection of the structure of 1,2-diarylethanols with the highest biological activity of lipopolysaccharides (LPS) in the model strains of Escherichia coli K12 (without LPS in its structure) and R2–R4 (with different lengths of LPS in its structure). In the presented studies, based on the conducted minimum inhibitory concentration (MIC) and MBC tests, it was demonstrated that the antibacterial (toxic) effect of 1,2-diarylethanols depends on their structure and the length of LPS bacteria in the membrane of specific strains. Moreover, the oxidative damage of bacterial DNA isolated from bacteria after modification with newly synthesized compounds after application of the repair enzyme Fpg glycosylases was analysed. The analysed damage values were compared with modification with appropriate antibiotics; bacterial DNA after the use of kanamycin, streptomycin, ciprofloxacin, bleomycin and cloxicillin. The presented research clearly shows that 1,2-diarylethanol derivatives can be used as potential candidates for substitutes for new drugs, e.g., the analysed antibiotics. Their chemical and biological activity is related to two aromatic groups and the corresponding chemical groups in the structure of the substituent. The observed results are particularly important in the case of increasing bacterial resistance to various drugs and antibiotics, especially in nosocomial infections and neoplasms, and in the era of pandemics caused by microorganisms.

COMPARATIVE STUDIES OF THE POTENTIATION OF CORTICOTROPHIN ACTIVITY BY SEVERAL INACTIVE DERIVATIVES

1963 ◽  
Vol 42 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Arthur I. Cohen ◽  
Edward H. Frieden
Keyword(s):  
Biological Activity ◽  
Comparative Studies ◽  
Free Amino ◽  
Hormonal Activity ◽  
Amino Groups

ABSTRACT A number of corticotrophin analogues have been prepared, some of which potentiate the biological activity of the untreated hormone in vitro. The free amino groups of corticotrophin appear to be essential not only for hormonal activity, but also for the interaction of the analogues with the tissue corticotrophin inactivating system which is assumed to account for the potentiating effect.

Large-scale High-throughput Screening Revealed 5'-(carbonylamino)-2,3'- bithiophene-4'-carboxylate as Novel Template for Antibacterial Agents

2020 ◽  
Vol 17 (5) ◽  
pp. 716-724
Author(s):  
Yan A. Ivanenkov ◽  
Renat S. Yamidanov ◽  
Ilya A. Osterman ◽  
Petr V. Sergiev ◽  
Vladimir A. Aladinskiy ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
High Throughput ◽  
High Throughput Screening ◽  
Large Scale ◽  
Antibacterial Agents ◽  
Sos Response ◽  
Luciferase Assay ◽  
Translational Machinery ◽  
E Coli ◽  
New Class

Background: The key issue in the development of novel antimicrobials is a rapid expansion of new bacterial strains resistant to current antibiotics. Indeed, World Health Organization has reported that bacteria commonly causing infections in hospitals and in the community, e.g. E. Coli, K. pneumoniae and S. aureus, have high resistance vs the last generations of cephalosporins, carbapenems and fluoroquinolones. During the past decades, only few successful efforts to develop and launch new antibacterial medications have been performed. This study aims to identify new class of antibacterial agents using novel high-throughput screening technique. Methods: We have designed library containing 125K compounds not similar in structure (Tanimoto coeff.< 0.7) to that published previously as antibiotics. The HTS platform based on double reporter system pDualrep2 was used to distinguish between molecules able to block translational machinery or induce SOS-response in a model E. coli system. MICs for most active chemicals in LB and M9 medium were determined using broth microdilution assay. Results: In an attempt to discover novel classes of antibacterials, we performed HTS of a large-scale small molecule library using our unique screening platform. This approach permitted us to quickly and robustly evaluate a lot of compounds as well as to determine the mechanism of action in the case of compounds being either translational machinery inhibitors or DNA-damaging agents/replication blockers. HTS has resulted in several new structural classes of molecules exhibiting an attractive antibacterial activity. Herein, we report as promising antibacterials. Two most active compounds from this series showed MIC value of 1.2 (5) and 1.8 μg/mL (6) and good selectivity index. Compound 6 caused RFP induction and low SOS response. In vitro luciferase assay has revealed that it is able to slightly inhibit protein biosynthesis. Compound 5 was tested on several archival strains and exhibited slight activity against gram-negative bacteria and outstanding activity against S. aureus. The key structural requirements for antibacterial potency were also explored. We found, that the unsubstituted carboxylic group is crucial for antibacterial activity as well as the presence of bulky hydrophobic substituents at phenyl fragment. Conclusion: The obtained results provide a solid background for further characterization of the 5'- (carbonylamino)-2,3'-bithiophene-4'-carboxylate derivatives discussed herein as new class of antibacterials and their optimization campaign.

Quality Improvement of the DNA extracted by boiling method in Gram negative bacteria

2017 ◽  
Vol 6 (04) ◽  
pp. 5347 ◽  
Author(s):  
Omar B. Ahmed* ◽  
Anas S. Dablool
Keyword(s):  
Dna Extraction ◽  
Control Method ◽  
Extraction Procedure ◽  
Cost Effective ◽  
High Yield ◽  
Gram Negative Bacteria ◽  
Bacterial Dna ◽  
Gram Negative ◽  
E Coli

Several methods of Deoxyribonucleic acid (DNA) extraction have been applied to extract bacterial DNA. The amount and the quality of the DNA obtained for each one of those methods are variable. The study aimed to evaluate bacterial DNA extraction using conventional boiling method followed by alcohol precipitation. DNA extraction from Gram negative bacilli was extracted and precipitated using boiling method with further precipitation by ethanol. The extraction procedure performed using the boiling method resulted in high DNA yields for both E. coli and K. pneumoniae bacteria in (199.7 and 285.7μg/ml, respectively) which was close to control method (229.3 and 440.3μg/ml). It was concluded that after alcohol precipitation boiling procedure was easy, cost-effective, and applicable for high-yield quality of DNA in Gram-negative bacteria.

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