scholarly journals The research of disinfective properties of kontravir for disinfection of veterinary objects

2019 ◽  
pp. 29-34
Author(s):  
O. Shkromada ◽  
Yu. Dudchenko ◽  
T. Necherya ◽  
I. Abubakari Kavla
Keyword(s):  
Water Flow Rate ◽  
Distilled Water ◽  
Metal Structures ◽  
E Coli ◽  
Metal Plates ◽  
Before And After ◽  
Corrosive Effect ◽  
Bacteria And Fungi ◽  
Micro Organisms ◽  
Emergence Of Resistance

In this field, complex disinfectants were contrasted using effective concentrations against bacteria and spore-forming microorganisms. A significant problem for the owners is the emergence of resistance of strains of microorganisms in the existing production and the same disinfectants. Investigation of trusted working concentrations of disinfectants that do not have a corrosive effect on metal structures. According to the results of research and production, contrast is an effective disinfectant for reducing E. coli and S aureus at 0,3 – 0,5% concentration at exposure for 30 min. and consumption of 100 - 400 cm3 / m2. Laboratory researches were carried out in laboratories of microbiological faculties of veterinary medicine of Sumy National Agrarian University. Disappearance gaps and disinfection on the market in Kyiv. Samples were drawn in the refrigerators from the walls, ceilings and floors. Refrigerated chambers made of stainless steel are made up of rubber and plastic elements. Metals are very vulnerable to corrosion with more concentrated acids and alkali. This was taken into account when choosing a disinfectant and its effective organizations. As a disinfectant used the drug contrast (manufacturer PE "Kronos Agro", Ukraine). The disinfectant was taken at a dose of 100 ml per 1 m2. To produce the culture was prepared basic products containing 1000 mg of the drug in 1 ml of distilled water. The experimental solutions were prepared for study with the main formulations developed. Representatives had extraordinary effects. The  disks were leaked through the disinfectant to obtain a zone of retention of high bacteria and fungi. The reliability of disinfectant destroying the micro-organisms of E. coli and S. aureus test cultures was also known. For the trusted production preparations, the contrast at the trusted enterprises was carried out by the rehabilitation of the premises of the educational laboratory of the Sumy National Agrarian University (premises for animals, dairies, refrigeration chambers). Renovation and test activities were performed at 0,1, 0,25 and 0,5 % of exposed contrast with exposure for 60, 30 and 10 min. the disinfectant was consumed 250 cm3 / m2. Upon completion of the studies, the investigated tests were investigated with distilled water (flow rate - 1000 cm3 / m2). Water that has been washed away test products, presented in specially prepared capabilities. Test results for this after disinfection were also investigated with distilled water, which was found on the disinfectant. To study the corrosion activity of the disinfectant used metal plates 1h1sm2. The metal samples were welded to the fifth mark after the commission before and after the study. 0,5; 1,0; 1,5; 2,5 % contrast solutions were used in the study. For comparison, in the experiments used 2% of productive. M. bovis mycobacterial cultures were grown on Pavlovsky's glycerol medium. The bacterial culture was transferred into sterile vials and sterile isotonic material containing 0,05 cm3 / mg was added. A large amount of delay zone in Petri dishes containing 0,5 % of S. aureus disinfectant, 3,5 times S. cholerase 1,8 S. Enteritidis 2 more than 0,5% formal form . Higher indicators of bacterial properties of the disinfectant contrast at a concentration of 0,5%.

scholarly journals Origins and control of bacterial contamination during spinal manipulation

2018 ◽  
Author(s):  
◽  
Fariya Amod
Keyword(s):  
Staphylococcus Aureus ◽  
Spinal Manipulation ◽  
Bacterial Flora ◽  
Positive Control ◽  
Viable Count ◽  
E Coli ◽  
Pseudomonas Spp ◽  
Significant Difference ◽  
Before And After ◽  
Micro Organisms

Background: Research has revealed that healthcare workers’ hands serve as a source and vehicle for the transmission of micro-organisms within the healthcare sector, thus resulting in nosocomial infections, better known as healthcare-associated infections. The chiropractic profession is traditionally known as a hands-on profession, where the fundamental treatment protocol includes manual manipulation of the spine. In order to perform these procedures hand-to-patient interaction is required, resulting in skin-to-skin contact. Poor hand hygiene practice has been attributed by the World Health Organization as the primary cause for the spread of micro-organisms within the healthcare environment. Unwashed hands harbour microbes, thus increasing contamination levels and subjecting patients to these potential pathogens. This study aimed to determine the presence and transfer of bacterial contamination occurring during spinal manipulation, as well as analysing the efficacy of decontaminants used by chiropractic practitioners against the isolated bacteria cultivated. Research design: The study was located in the quantitative experimental paradigm and conducted as a cross-sectional investigation. Method: Samples were obtained from chiropractors’ hands before and after spinal manipulation. Samples were then serially diluted, plated in duplicate (using the spread plate technique) and incubated for 24-48 hours at 37°C. Viable counts of colony forming units (CFUs) were then enumerated in order to verify the presence of bacteria on the chiropractors’ hands, as well as to establish the direction of transfer occurring during spinal manipulation. Macroscopic and microscopic characteristics of each bacterial isolate were used to identify the bacteria cultivated. A modified Kirby Bauer technique was used to ascertain the efficacy of decontaminants commonly used by chiropractors, against the isolated bacteria obtained from their hands. Results: Bacterial flora were present on 100% of the chiropractors hands both pre- and post-spinal manipulation. A mean of 16,456 (27,718) cfu/ml⁻¹ were enumerated from the samples collected from the chiropractors’ hands during manipulation. A paired t-test indicated a significant difference noted in the viable count of bacteria found on the chiropractors’ hands before and after manipulation (p<0.001). A significant difference was observed in the viable count of bacteria post-manipulation (70%), as opposed to the pre- manipulation readings (30%).This was indicative of a higher rate of bacteria being transferred from the patient to the chiropractor during spinal manipulation. The majority of the microorganisms identified were either primary or opportunistic pathogens. Staphylococci were most prevalent in the pre-spinal manipulation readings accounting for 53% of the colonies, followed by micrococci with 39%, bacilli with 4%, Staphylococcus aureus with 3% and streptococci with 1%. Pseudomonas spp. were present but uncommon. Escherichia coli were not present on the chiropractors’ hands in any of the samples obtained pre-manipulation. The post-manipulation readings constituted a high prevalence of micrococci accounting for 57% of the colonies, followed by staphylococci with 32%, Pseudomonas spp. with 5%, E. coli with 3%, Staphylococcus aureus with 2% and bacilli with 1%. Streptococci were present but uncommon. The decontaminants tested were most effective against gram-positive bacteria such as Bacillus, Micrococcus, Staphylococcus, Staphylococcus aureus and Streptococcus. The bacteria isolated were most susceptible to the D-Germ hand disinfectant, while the Dis-Chem instant hand sanitizer was the least effective decontaminant tested. Ciprofloxacin was the antibiotic used as a positive control. A significant difference was noted between the performance of the positive control and the decontaminants on the bacteria isolated. Conclusions and recommendations: The study proved the presence of primary and opportunistic pathogens found on the chiropractors’ hands. These included Staphylococcus spp., Micrococcus spp., Bacillus spp., Pseudomonas spp., E. coli, Streptococcus spp. and Staphylococcus aureus. A higher rate of bacteria was observed being transferred from the patient to the chiropractor during spinal manipulation. The majority of the microorganisms identified were either primary or opportunist pathogens, thus predisposing both the patient and the chiropractor to potential infection. A significant difference was noted between the performance of the positive control and the decontaminants on the bacteria isolated. None of the decontaminants were as effective against the bacteria isolated as the positive control. It can therefore be deduced that each bacterial flora was not removed by some of the decontaminants currently used by chiropractic practitioners in practice.

Antibacterial Activities of Biosynthesized ZnO Nanoparticles Using Leaf and Fruit Extracts of Neolamarckia cadamba

2021 ◽  
Vol 21 (12) ◽  
pp. 6168-6182
Author(s):  
Saee Gharpure ◽  
Rachana Yadwade ◽  
Shuana Mehmood ◽  
Balaprasad Ankamwar
Keyword(s):  
Antibacterial Activity ◽  
Zno Nanoparticles ◽  
Leaf Extract ◽  
Antibacterial Properties ◽  
Fruit Extract ◽  
E Coli ◽  
Fruit Extracts ◽  
Before And After ◽  
Micro Organisms ◽  
Antibacterial Potential

Zinc oxide nanoparticles have been biosynthesized with the help of Neolamarckia cadamba leaf and fruit extracts. ZnO nanoparticles were tested for antibacterial activity before and after calcination against Gram positive (Staphylococcus aureus, Bacillus subtilis) as well as Gram negative micro-organisms (Escherichia coli, Pseudomonas aeruginosa) within the concentration range 0.625–10 mg/mL with the help of well diffusion technique. Higher antibacterial potential has been observed in ZnO nanoparticles synthesized using leaf extract in comparison with those synthesized using fruit extract. Increased antibacterial activity was observed before calcination as compared to after calcination. ZnO synthesized using leaf extract were observed to show significant antibacterial potential against E. coli, S. aureus along with P. aeruginosa before calcination as well as against E. coli after calcination. Similarly, ZnO nanoparticles synthesized using fruit extract exhibited antibacterial activity against E. coli and P. aeruginosa before calcination and against E. coli after calcination. Both the ZnO nanoparticles before and after calcination did not show any antibacterial activity against B. subtilis. Thus, ZnO nanoparticles can serve a dual purpose by its application as an antibacterial agent against susceptible micro-organisms as well as biocompatible carrier system for drug delivery applications in case of non-antibacterial properties by virtue of its inertness as well as easy disposal.

Non-Antibacterial and Antibacterial ZnO Nanoparticles Composed of Different Surfactants

2021 ◽  
Vol 21 (12) ◽  
pp. 5945-5959
Author(s):  
Saee Gharpure ◽  
Tushar Jadhav ◽  
Chetan Ghotekar ◽  
Anuja Jagtap ◽  
Yogita Vare ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Zinc Oxide Nanoparticles ◽  
Zno Nps ◽  
Minimum Concentration ◽  
Gram Negative ◽  
E Coli ◽  
Therapeutic Drugs ◽  
Before And After ◽  
Micro Organisms ◽  
Triton X

Zinc oxide nanoparticles were synthesized using different surfactants such as SDS, CTAB, Triton X-100, PVP K-30 and ethylene glycol. ZnO NPs were tested for antibacterial activity before and after calcination against different micro-organisms like E. coli and P. aeruginosa (Gram negative) as well as S. aureus and B. subtilis (Gram positive). Antibacterial activity was observed in SDScapped ZnO NPs only against B. subtilis. Antibacterial activity of ZnO-capped SDS was tested in a concentration range 0.625–10 mg/mL. Increased antibacterial activity was observed before calcination as compared to after calcination. Minimum concentration at which uncalcinated as well as calcinated SDS-capped ZnO NPs show antibacterial activity is 2.5 mg/mL and 5 mg/mL respectively. Non-antibacterial nature of ZnO NPs highlights its further use in drug delivery due to its inert nature, enhanced efficacy in association with therapeutic drugs as well as easy disposal.

scholarly journals The Effect of Acetic Acid Treatments on the Quality of Stored Carrot (Daucus carota L.) Seeds

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1176
Author(s):  
Hanna Dorna ◽  
Agnieszka Rosińska ◽  
Dorota Szopińska
Keyword(s):  
Acetic Acid ◽  
Distilled Water ◽  
Storage Duration ◽  
Seed Vigour ◽  
Daucus Carota L ◽  
Two Samples ◽  
Before And After ◽  
Alternaria Dauci ◽  
Acid Treatments

Alternaria dauci (J.G. Kühn) J.W. Groves et Skolko and A. radicina Meier, Drechsler et E.D. Eddy are important seed-transmitted pathogens of carrot. The aim of this study was to evaluate the effects of acetic acid treatments on the quality of stored carrot seeds. Seeds of two samples were soaked for 30 min in 0.5, 1 and 2% acetic acid. Controls included untreated seeds, seeds soaked in distilled water and seeds treated with fungicide Zaprawa Nasienna T 75 WS/DS (a.i. thiram 75%). Germination, vigour and health of untreated and treated seeds were evaluated before and after 5 and 12 months of storage at 4 and 20 °C. Seeds of both samples treated with 0.5 and 1% acetic acid were characterized by higher germination capacity after storage than untreated seeds. However, treatments with 1 and 2% acetic acid negatively affected seed vigour. Generally, seeds of both samples treated with acetic acid were characterized by lower infestation with A. alternata and A. radicina after storage than untreated seeds and seeds soaked in distilled water. Moreover, acetic acid often controlled these fungi more effectively than the fungicide. Regardless of the storage duration, infestation with fungi was higher if seeds of both samples were stored at a lower temperature.

scholarly journals Antimicrobial Activity of Cationic Poly(3-hexylthiophene) Nanoparticles Coupled with Dual Fluorescent and Electrochemical Sensing: Theragnostic Prospect

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1715
Author(s):  
Nada Elgiddawy ◽  
Shiwei Ren ◽  
Wadih Ghattas ◽  
Waleed M. A. El Rouby ◽  
Ahmed O. El-Gendy ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Fluorescence Spectroscopy ◽  
Bacterial Infections ◽  
Electrochemical Impedance ◽  
Spectroscopic Properties ◽  
Electrochemical Sensing ◽  
E Coli ◽  
Normal Human ◽  
Dual Detection ◽  
Bacteria And Fungi

Designing therapeutic and sensor materials to diagnose and eliminate bacterial infections remains a significant challenge for active theragnostic nanoprobes. In the present work, fluorescent/electroactive poly(3-hexylthiophene) P3HT nanoparticles (NPs) stabilized with quaternary ammonium salts using cetyltrimethylammonium bromide (CTAB), (CTAB-P3HT NPs) were prepared using a simple mini-emulsion method. The morphology, spectroscopic properties and electronic properties of CTAB-P3HT NPs were characterized by DLS, zeta potential, SEM, TEM, UV-vis spectrophotometry, fluorescence spectroscopy and electrochemical impedance spectroscopy (EIS). In an aqueous solution, CTAB-P3HT NPs were revealed to be uniformly sized, highly fluorescent and present a highly positively charged NP surface with good electroactivity. Dual detection was demonstrated as the binding of the bacteria to NPs could be observed by fluorescence quenching as well as by the changes in EIS. Binding of E. coli to CTAB-P3HT NPs was demonstrated and LODs of 5 CFU/mL and 250 CFU/mL were obtained by relying on the fluorescence spectroscopy and EIS, respectively. The antimicrobial activity of CTAB-P3HT NPs on bacteria and fungi was also studied under dark and nutritive conditions. An MIC and an MBC of 2.5 µg/mL were obtained with E. coli and with S. aureus, and of 0.312 µg/mL with C. albicans. Additionally a good biocompatibility toward normal human cells (WI38) was observed, which opens the way to their possible use as a therapeutic agent.

Hydrothermal Generation of 3-Dimensional WO3 Nanocubes, Nanobars and Nanobricks, Their Antimicrobial and Anticancer Properties

2021 ◽  
Vol 21 (10) ◽  
pp. 5337-5343
Author(s):  
Nilam Qureshi ◽  
Seungjae Lee ◽  
Ravindra Chaudhari ◽  
Pramod Mane ◽  
Jayant Pawar ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Growth Curves ◽  
Viable Cell ◽  
Inhibition Zone ◽  
Bacterial Cells ◽  
Hydrothermal Route ◽  
3 Dimensional ◽  
Anticancer Properties ◽  
Bacteria And Fungi ◽  
Micro Organisms

In our current endeavor, 3-dimensional (3D) tungsten oxide (WO3) nanostructures (nanocubes, nanobars and nanobricks) have been swiftly generated via hydrothermal route at 160 °C for 24 h. Physico-chemical characterization of the resultant powder revealed formation of WO3 nanostructures with predominantly faceted cube, brick and rectangular bar-like morphology. The present study was also aimed at exploring the antimicrobial and anticancer potential of WO3 nanostructures. Antimicrobial activity was tested against different micro-organisms viz., Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Aspergillus fumigatus. The antibacterial and antifungal activity was ascertained against these micro-organisms by measuring the diameter of inhibition zone in agar well diffusion test which revealed that the resultant WO3 nanostructures acted as excellent antibacterial agents against both bacteria and fungi but were more effective against the fungus, A. fumigatus. To examine the growth curves of bacterial cells, time kill assay was monitored for E. coli, against which significant antibacterial action of WO3 nanostructures was noted. The anti-cancer activity of WO3 nanostructures was found to be concentration-dependent against KB cell line by viable cell count method. In our pilot study, WO3 nanostructures suspension with concentration in the range of 10−1 to 10−5 mg/ml was found to kill KB cells effectively.

Experiments on Substrate Selection by Corophium Species: Films and Bacteria on Sand Particles

1964 ◽  
Vol 41 (3) ◽  
pp. 499-511
Author(s):  
P. S. MEADOWS
Keyword(s):  
Ionic Strength ◽  
Sea Water ◽  
Distilled Water ◽  
Substrate Selection ◽  
Corophium Volutator ◽  
Simple Method ◽  
Substrate Preferences ◽  
Solutions Of Electrolytes ◽  
Sand Particles ◽  
Micro Organisms

1. A simple method is described for determining the substrate preferences of Corophium volutator (Pallas) and Corophium arenarium Crawford. 2. If offered a choice of its own substrate with that of the other species each prefers its own. 3. Level of illumination and colour of substrate have little effect on choice. An animal's size and hence its age has little effect on its substrate preferences. 4. C. volutator prefers a substrate previously maintained under anaerobic conditions, C. arenarium vice versa. 5. Treatments which kill, inactivate, or remove micro-organisms render sands unattractive to Corophium. These include boiling, acid-cleaning, drying, and soaking in fixatives or distilled water. Attempts to make these sands attractive again failed. 6. Distilled water, and solutions of the non-electrolytes sucrose and glycerol at the same osmotic pressure as sea water, induce many bacteria to desorb from sand particles; smaller numbers are desorbed in the presence of solutions of electrolytes at the same ionic strength as sea water (NaCl, Na2SO4, KC1, MgSO4, MgCl2, CaCl2). Of all these, only distilled water and solutions of MgCl2 and CaCl2 reduce the attractive properties of sands. Hence the loss of bacteria from the surface of sand grains, though related to the ionic strength and composition of the medium, is not necessarily associated with a substrate becoming unattractive.

A Comparison of Hand Washing Techniques To Remove Escherichia coli and Caliciviruses under Natural or Artificial Fingernails

2003 ◽  
Vol 66 (12) ◽  
pp. 2296-2301 ◽  
Author(s):  
CHIA-MIN LIN ◽  
FONE-MAO WU ◽  
HOI-KYUNG KIM ◽  
MICHAEL P. DOYLE ◽  
BARRY S. MICHAELS ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Tap Water ◽  
Hand Washing ◽  
Microbial Populations ◽  
Liquid Soap ◽  
E Coli ◽  
Hand Sanitizer ◽  
Before And After ◽  
Escherichia Coli Jm109 ◽  
Viral Indicators

Compared with other parts of the hand, the area beneath fingernails harbors the most microorganisms and is most difficult to clean. Artificial fingernails, which are usually long and polished, reportedly harbor higher microbial populations than natural nails. Hence, the efficacy of different hand washing methods for removing microbes from natural and artificial fingernails was evaluated. Strains of nonpathogenic Escherichia coli JM109 and feline calicivirus (FCV) strain F9 were used as bacterial and viral indicators, respectively. Volunteers with artificial or natural nails were artificially contaminated with ground beef containing E. coli JM109 or artificial feces containing FCV. Volunteers washed their hands with tap water, regular liquid soap, antibacterial liquid soap, alcohol-based hand sanitizer gel, regular liquid soap followed by alcohol gel, or regular liquid soap plus a nailbrush. The greatest reduction of inoculated microbial populations was obtained by washing with liquid soap plus a nailbrush, and the least reduction was obtained by rubbing hands with alcohol gel. Lower but not significantly different (P &gt; 0.05) reductions of E. coli and FCV counts were obtained from beneath artificial than from natural fingernails. However, significantly (P ≤ 0.05) higher E. coli and FCV counts were recovered from hands with artificial nails than from natural nails before and after hand washing. In addition, microbial cell numbers were correlated with fingernail length, with greater numbers beneath fingernails with longer nails. These results indicate that best practices for fingernail sanitation of food handlers are to maintain short fingernails and scrub fingernails with soap and a nailbrush when washing hands.

Survival of cryptosporidium parvum, escherichia coli, faecal enterococci and clostridium perfringens in river water: influence of temperature and autochthonous microorganisms

1997 ◽  
Vol 35 (11-12) ◽  
pp. 249-252 ◽  
Author(s):  
G. J. Medema ◽  
M. Bahar ◽  
F. M. Schets
Keyword(s):  
Surface Water ◽  
River Water ◽  
Cryptosporidium Parvum ◽  
Health Hazard ◽  
Influence Of Temperature ◽  
E Coli ◽  
Untreated Water ◽  
Time Required ◽  
Micro Organisms

Oocysts of Cryptosporidium parvum can survive for several months in surface water, one of the main factors determining their success in environmental transmission and thus their health hazard via water. Several factors in the environment, e.g. temperature, presence of predators and exo-enzymes will probably influence oocyst survival. The high persistence of oocysts may also limit the value of traditional faecal indicator bacteria. The aim of this study was to determine the rate at which C parvum oocysts, E coli, faecal enterococci and C perfringens spores die in surface water and the influence of temperature and the presence of autochthonous (micro)organisms on the die-off rate. Microcosms with autoclaved river water were inoculated with the organisms. Microcosms with untreated river water were inoculated with concentrated primary effluent containing the bacteria and with C parvum oocysts. Microcosms were incubated at 5°C or 15°C at 100rpm. Viability of oocysts was monitored by in vitro excystation and dye-exclusion; viability of the bacteria was determined on appropriate selective media. When pseudo first-order die-off kinetics were assumed, the die-off rate of oocysts at 5°C was 0.010 log10/d and at 15°C, 0.006–0.024 log10/d. These rates underestimate die-off since oocyst disintegration was not accounted for. Incubation in autoclaved or untreated water did influence the die-off rate of oocysts at 15°C but not at 5°C. The die-off rate of E coli and enterococci was faster in the non-sterile river water than in autoclaved water at both temperatures. At 15°C, E coli (and possibly E faecium) even multiplied in autoclaved water. In untreated river water, the die-off of E coli and enterococci was approximately 10x faster than die-off of oocysts but die-off rates of C perfringens were lower than those of oocysts. As for oocysts, die-off of the bacteria and spores was faster at 15°C than at 5°C. Oocysts are very persistent in river water: the time required for a 10x reduction in viability being 40–160d at 15°C and 100d at 5°C. Biological/biochemical activity influenced oocyst survival at 15°C and survival of both vegetative bacteria at 5 and 15°C. The rapid die-off of E coli and enterococci makes them less suitable as indicators of oocyst presence in water. As C perfringens survived longer in untreated river water than oocysts, it may prove useful as an indicator of the presence of C parvum.

The HiPIP from the acidophilic Acidithiobacillus ferrooxidans is correctly processed and translocated in Escherichia coli, in spite of the periplasm pH difference between these two micro-organisms

Microbiology ◽  
2005 ◽  
Vol 151 (5) ◽  
pp. 1421-1431 ◽  
Author(s):  
Patrice Bruscella ◽  
Laure Cassagnaud ◽  
Jeanine Ratouchniak ◽  
Gaël Brasseur ◽  
Elisabeth Lojou ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Acidithiobacillus Ferrooxidans ◽  
Biochemical Properties ◽  
Gene Encoding ◽  
Iron Sulfur Cluster ◽  
E Coli ◽  
Iron Sulfur ◽  
Sulfur Protein ◽  
Tat System ◽  
Micro Organisms

The gene encoding a putative high-potential iron–sulfur protein (HiPIP) from the strictly acidophilic and chemolithoautotrophic Acidithiobacillus ferrooxidans ATCC 33020 has been cloned and sequenced. This potential HiPIP was overproduced in the periplasm of the neutrophile and heterotroph Escherichia coli. As shown by optical and EPR spectra and by electrochemical studies, the recombinant protein has all the biochemical properties of a HiPIP, indicating that the iron–sulfur cluster was correctly inserted. Translocation of this protein in the periplasm of E. coli was not detected in a ΔtatC mutant, indicating that it is dependent on the Tat system. The genetic organization of the iro locus in strains ATCC 23270 and ATCC 33020 is different from that found in strains Fe-1 and BRGM. Indeed, in A. ferrooxidans ATCC 33020 and ATCC 23270 (the type strain), iro was not located downstream from purA but was instead downstream from petC2, encoding cytochrome c 1 from the second A. ferrooxidans cytochrome bc 1 complex. These findings underline the genotypic heterogeneity within the A. ferrooxidans species. The results suggest that Iro transfers electrons from a cytochrome bc 1 complex to a terminal oxidase, as proposed for the HiPIP in photosynthetic bacteria.

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