scholarly journals Novel Expression Vector for Secretion of Cecropin AD in Bacillus subtilis with Enhanced Antimicrobial Activity

2009 ◽  
Vol 53 (9) ◽  
pp. 3683-3689 ◽  
Author(s):  
Xiang Chen ◽  
Faming Zhu ◽  
Yunhe Cao ◽  
Shiyan Qiao

ABSTRACT Cecropin AD, a chimeric antimicrobial peptide obtained from cecropins, is effective at killing specific microorganisms. However, a highly efficient expression system is still needed to allow for commercial application of cecropin AD. For the exogenous expression of cecropin AD, we fused the cecropin AD gene with a small ubiquitin-like modifier (SUMO) gene and a signal peptide of SacB, while a Bacillus subtilis expression system was constructed based on Bacillus subtilis cells genetically modified by the introduction of an operon including an isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible Spac promoter, a signal peptide of amyQ, and the SUMO protease gene. The recombinant cecropin AD was expressed, and 30.6 mg of pure recombinant protein was purified from 1 liter of culture supernatant. The purified cecropin AD displayed antimicrobial activity against some pathogens, such as Staphylococcus aureus and Escherichia coli, and was especially effective toward Staphylococcus aureus, with MICs of <0.05 μM (0.2 μg/ml). Stability analysis results showed that the activity of cecropin AD was not influenced by temperatures as high as 55°C for 20 min; however, temperatures above 85°C (for 20 min) decreased the antimicrobial activity of cecropin AD. Varying the pH from 4.0 to 9.0 did not appear to affect the activity of cecropin AD, but some loss of potency was observed at pH values lower than pH 4.0. Under the challenge of several proteases (proteinase K, trypsin, and pepsin), cecropin AD maintained functional activity. The results indicated that the recombinant product expressed by the designed Bacillus subtilis expression system was a potent antimicrobial agent and could be applied to control infectious diseases of farm animals or even humans.

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Hussein A Kadhum ◽  
Thualfakar H Hasan2

The study involved the selection of two isolates from Bacillus subtilis to investigate their inhibitory activity against some bacterial pathogens. B sub-bacteria were found to have a broad spectrum against test bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. They were about 23-30 mm and less against Klebsiella sp. The sensitivity of some antibodies was tested on the test samples. The results showed that the inhibitory ability of bacterial growth in the test samples using B. subtilis extract was more effective than the antibiotics used.


2018 ◽  
Vol 13 (4) ◽  
pp. 1934578X1801300
Author(s):  
Daniyar Sadyrbekov ◽  
Timur Saliev ◽  
Yuri Gatilov ◽  
Ivan Kulakov ◽  
Roza Seidakhmetova ◽  
...  

A cyclopropane derivative of limonene, (1 S, 4 S, 6 R)-7,7-dichloro-4-[(1 S)-2,2-dichloro-1-methylcyclopropyl]-1-methylbicyclo [4.1.0] heptane (compound 2), was synthesized and its structure was determined by NMR and X-ray crystallographic methods. In addition, an antimicrobial activity of the compound against Gram-positive ( Staphylococcus aureus, Bacillus subtilis) and Gram-negative ( Escherichia coli, Pseudomonas aeruginosa) bacterial strains was also scrutinized.


2006 ◽  
Vol 61 (5-6) ◽  
pp. 319-323 ◽  
Author(s):  
Mehmet Candan ◽  
Meral Yılmaz ◽  
Turgay Tay ◽  
Merih Kıvança ◽  
Hayrettin Türk

The antimicrobial activity of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Xanthoparmelia pokornyi and its gyrophoric acid and stenosporic acid constituents has been screened against some foodborne bacteria and fungi. Both the extracts and the acids showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans and Candida glabrata. The extracts were inactive against the tested filamentous fungi. The MIC values of the extracts and the acids for the bacteria have also been determined.


Medicina ◽  
2008 ◽  
Vol 44 (12) ◽  
pp. 977 ◽  
Author(s):  
Alvydas Pavilonis ◽  
Algirdas Baranauskas ◽  
Ligita Puidokaitė ◽  
Žaneta Maželienė ◽  
Arūnas Savickas ◽  
...  

Objective. To evaluate the antimicrobial activity of soft and purified propolis extracts. Study object and methods. Antimicrobial activity of soft and purified propolis extracts was determined with reference cultures of Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 33499, Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis ATCC 12459, Bacillus subtilis ATCC 6633, Bacillus cereus ATCC 8035, and fungus Candida albicans ATCC 60193. Microbiological tests were performed under aseptic conditions. Minimum inhibitory concentration (MIC) – the highest dilution of preparation (the lowest concentration of preparation) that suppresses growth of reference microorganisms – was determined. Results. Concentration of phenolic compounds in soft propolis extract that possesses antimicrobial activity against gram-positive (Staphylococcus aureus, Enterococcus faecalis) and gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis) is 0.587±0.054 mg and 0.587±0.054–0.394±0.022 mg (P>0.05) and in purified propolis extract – 0.427±0.044 mg and 0.256±0.02 mg (P>0.05). Klebsiella pneumoniae is most resistant to soft propolis extract when the concentration of phenolic compounds is 1.119± 0.152 mg and to purified propolis extract when the concentration of phenolic compounds is 1.013±0.189 mg (P>0.05). Spore-forming Bacillus subtilis bacteria are more sensitive to soft and purified propolis extracts when the concentration of phenolic compounds is 0.134±0.002 mg and 0.075±0.025 mg, respectively, and Bacillus cereus – when the concentration is 0.394±0.022 mg and 0.256±0.02 mg (P>0.05). Sensitivity of fungus Candida albicans to soft and purified propolis extracts is the same as Bacillus subtilis. Encapsulated bacterium Klebsiella pneumoniae is most resistant to antimicrobial action of soft and purified propolis extracts as compared with gram-positive Staphylococcus aureus and Enterococcus faecalis bacteria (P<0.05), gram-negative Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis (P<0.05), sporeforming Bacillus subtilis and Bacillus cereus bacteria (P<0.05), and fungus Candida albicans (P<0.05). There is no statistically significant difference between antimicrobial effect of soft propolis extract and purified propolis extract on gram-positive bacteria, gram-negative bacteria, spore-forming bacteria, encapsulated bacteria, and Candida fungus. Conclusions. Soft and purified propolis extracts possess antimicrobial activity. They could be recommended as natural preservatives in the manufacture of pharmaceutical products.


2004 ◽  
Vol 59 (5-6) ◽  
pp. 384-388 ◽  
Author(s):  
Turgay Tay ◽  
Ayşen Özdemir Türk ◽  
Meral Yılmaz ◽  
Hayrettin Türk ◽  
Merih Kıvanç

The acetone extract of the lichen Ramalina farinacea and its (+)-usnic acid constituent showed antimicrobial activity against Bacillus subtilis, Listeria monocytogenes, Proteus vul­garis, Staphylococcus aureus, Streptococcus faecalis. Yersinia enterocolitica, Candida albicans, and Candida glabrata. Norstictic acid was active against Aeromonas hydrophila as well as the above microorganisms except Yersinia enterocolitica. Protocetraric acid showed activity only against the tested yeasts Candida albicans and Candida glabrata. The MIC values of the extract as well as of the three substances were determined. No antifungal activity of the acetone extract has been observed against ten filamentous fungi.


2020 ◽  
Vol 1 (2) ◽  
pp. 41-45
Author(s):  
A.Suparlan Isya Syamsu

Preliminary research has been conducted on the antimicrobial activity of n-Butanol extract of forest honey (Apis nigrocincta). This study aims to determine the antimicrobial activity of forest honey from Selayar Regency on the growth of test microbes, using the method of solid dilution with the test microbial Bacillus subtilis, Staphylococcus aureus, Streptococcus mutans, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, Vibrio sp, Staphylococcus epidermidis, and Candida albicans against n-butanol extract from forest honey (Apis nigrocincta) at 1 mg/ml. The results obtained showed that n-butanol extract inhibited the growth of bacteria Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and Staphylococcus aureus. To estimate the compounds that provide antimicrobial activity, the TLC-Bioautography test is performed. Obtained the best results from the separation of compounds by TLC using Chlorophorom eluate: Acetone (3: 1). The TLC-Bioautographic test results showed that the spots with an Rf value of 0.29 gave activity to Bacillus subtilis, Escherichia coli, and Staphylococcus epidermidis, and gave positive results on the appearance of flavonoid compounds.


2015 ◽  
Vol 1 (2) ◽  
pp. 126
Author(s):  
Urnemi ◽  
Sumaryati Syukur ◽  
Endang Purwati ◽  
Sanusi Ibrahim ◽  
Jamsari

ABSTRACT Lactic acid bacteria (LAB) were isolated from of cocoa beans fermentation Forestero variety from West Sumatera, that were eleven isolates. The isolates were tested to antimicrobial activity against pathogenic bacteria E.coli NBRC 14237, Staphylococcus aureus NBRC 13276, Bacillus subtilis BTCCB 612, listeria m. dan S. Typhii. Results the research showed that, isolates had inhibition zone to pathogenic bacteria, that were 7 mm till 12 mm at 48 hours observation. R2.4 isolate was most potential to inhibition zones growth pathogenic bacteria, that was 11mm till 12 mm to five pathogens. R2.4 isolates was the highest to against pathogenic bacteria (Bacillus subtilis BTCCB, Listeria monocytogenesis and Staphylococcus aureus NBRC) had inhibition zones, that was 12.00 mm till 48 hours. Listeria monocytogenesis had been known as pest bacterium of food born, so that R2.4 isolate can be used as food biopreservative. Crude of R2.4 isolate molecular weight was 10 kDa by SDS-PAGE.  Key words: Lactic acid bacteria, Antimicrobial activity, SDS-PAGE, Cocoa fermentation and food biopreservative                                                      


Sign in / Sign up

Export Citation Format

Share Document