scholarly journals Plasmid Profiling and Effect of Different Physiological Parameters on the Chromium Reduction Potential of Microbes

2020 ◽  
Vol 1 (2) ◽  
pp. 19-31
Author(s):  
Masooma Mahzer ◽  
Mawra Gohar ◽  
Sumaira Mazher

Chromium is toxic for both human and aquatic life. It is recommended to eradicate from wastewaters or to alter its oxidation state to less toxic level The purpose of current research was to isolate heavy metal (Cr) resistant bacteria from different industrial effluents (soil and waste water), to determine their potential for chromium reduction (CRP) at different parameters (time period, pH, temperature and concentrations of chromium) and to determine the plasmid profiles of Cr (VI) resistant bacterial isolates. The growth of chromium resistant bacteria was determined by checking the influence of pH, concentration of chromium, time period and temperature on isolates using UV spectrophotometer, while chromium reduction potential was also investigated using Deleo and Ehrlich method. Plasmid profiling was performed and analyzed using agarose gel electrophoresis (0.8%) to determine the number, size and relationship of plasmid with heavy metal resistance. Results showed that the identified bacterial isolates (S. aureus and S. epidermidis) were resistant to heavy metal (Cr) confirmed by resistance profiling. The maximum growth of bacterial isolate was recorded after 24-hour incubation period (1.154), at pH 8 (1.512), temperature 37ºC (1.615) and 500 µg/mL chromium concentration (1.978), while suitable conditions observed for chromium reduction potential was 24-hour incubation period (57%), pH 7 (62.6%), temperature 30ºC (60%), and 500 µg/mL concentration of chromium (60%). The plasmid profiles revealed that plasmid were randomly distributed among the bacterial isolates with average plasmid number (2.9) ranging from 0-5 and molecular size (100-12000bps). Overall, no defined relationship was observed among resistance pattern and plasmid mediated profiles.

Author(s):  
Busayo Mutiat Olowe ◽  
Olufunke Adelegan

Background: The quest for potability of drinking water in various homes led to the widely use of chlorine or chlorine compound in treatment of water. Which however has contributed to increasing incidences of antibiotic resistance in the environment. Aim: This study aimed to investigate the microbial reduction potential and contribution of Sodium hypochlorite, NaOCl, to incidence of stress response genes in antibiotic-resistant bacteria. Study Design: Experimental Design was adopted in this study Place and Duration of the Study: The study was carried out at the Department of Microbiology, Faculty of Science, Ekiti State University between October, 2019 and February, 2020. Methodology: Sixteen (16) different water samples were randomly collected from various homes in Ajilosun, Ado-Ekiti and were chlorinated following manufacturer’s instruction. Microbial load of both raw and chlorinated water was determined using standard pour plate technique. Standard streaking method was used to isolate bacteria from chlorinated water samples. Standard CLSI technique was used to test the sensitivity of isolates to different antibiotics and PCR technique was employed to detect stress response genes (RpoS, RpoN, KatF genes) in multiple antibiotic-resistant bacterial isolates. Results: The result showed 24% and 52% reduction in the microbial load of well and pipe-borne water samples respectively following treatment with NaOCl for 180 sec. The different identified bacterial isolates recovered from chlorinated water samples included Enterobacter aerogenes (7.14 %), Proteus vulgaris (10.71 %), Escherichia coli (25 %), Bacillus cereus (32.14 %), Bacillus licheniformis (14.29 %) and Staphylococcus aureus (10.70 %). The bacterial isolates demonstrated varying resistance pattern to the different antibiotics. RpoS, RpoN and KatF genes encoding stress responses were detected in some of the tested antibiotic-resistant isolates. Conclusion: The study therefore stresses the importance of chlorination in contributing to increasing incidence of resistance of bacteria to stressors in the environment. Hence, subverting chlorination efficacy in treatment of water.


2020 ◽  
Vol 5 (3) ◽  
Author(s):  
Fahruddin Fahruddin ◽  
Nur Haedar ◽  
Slamet Santosa ◽  
Sri Wahyuni

Industrial progress and waste of urban domestic activities have an impact on the Pb heavy metal pollution on the environment, this will have an impact on human health. Pb metal can be overcome with biological methods by utilizing bacteria in reducing Pb metal. The study aimed to obtain the species  of resistant bacterial isolates of Pb metal and determine its characteristics. Sediment and water samples were obtained from the Tallo River. Isolation and selection of Pb metal resistant bacteria were carried out on nutrient agar media is 10 ppm added of PbAgNO3, afterwards the colonies that grew and differed were characterized by morphological morphology and several biochemical tests. The characterization results obtained 8 isolates of Pb metal resistant bacteria consisted of 8 isolates from sediment samples and 3 isolates from water samples. The characteristics of each bacterial isolate on cell morphology are the same and biochemical tests show different results.


2020 ◽  
Vol 6 (2) ◽  
pp. 112-119
Author(s):  
Rahmad Lingga ◽  
Budi Afriyansyah

Tin mining activity at sea has a various negative influence on the environment. One of them is heavy metal contamination that can affect the life of fisheries biota. This research conducted to isolate and test the Cu heavy metal resistance of marine sediment bacteria that are affected by tin mining activity. Sediment sampling was carried out in the area of tin mining to the mudflat neared to the mangrove area. Bacterial isolation was carried out by spread plate method and bacterial characterization included cell shape, Gram staining and biochemical tests. Furthermore, bacterial isolates tested for resistance to metals with concentrations of 10 ppm, 20 ppm, 40 ppm, 80 ppm and 100 ppm. The results showed that bacterial isolates originating from marine sediments affected by mining activity were resistant to Cu heavy metal at various concentrations. Isolates B6, B8 and A10 showed the highest resistance up to a concentration of 100 ppm


Author(s):  
Melkamu T. Addisu ◽  
Adugna M. Bikila

<p class="abstract"><strong>Background:</strong> The quality of life on earth is linked inseparably to the overall quality of the environment. Soil pollution with heavy metals has become a critical environmental concern due to its potential adverse ecological effects. The study explored the heavy metals resistance properties of bacteria isolated from fertilizer applied agricultural and non-agricultural soils.</p><p class="abstract"><strong>Methods:</strong> The soil samples were collected from both fertilizer applied agricultural soils and non-agricultural soils. After identification and characterization of the isolates from both soil types, six (6) similar bacterial isolates were selected to screen for resistance against Cobalt (Co<sup>+</sup>), Lead (Pb<sup>2+</sup>), Cromium (Cr<sup>+3</sup>), Mercury (Hg<sup>2+</sup>), Nickel (Ni<sup>2+</sup>), Cadmium (Cd<sup>2+</sup>) and Zinc (Zn<sup>2+</sup>) heavy metals. The minimum inhibitory concentration (MIC) for the bacterial isolates were determined by gradually increasing the concentration of heavy metals on agar plates until the isolates failed to show growth.  </p><p class="abstract"><strong>Results:</strong> The isolates from fertilizer applied agricultural soil showed the highest resistance against the selected heavy metals than those isolated from fertilizers not applied (nonagricultural) soils.</p><p><strong>Conclusions:</strong> From this result it can be seen that fertilizer has significant role in influencing the heavy metal resistance properties of bacteria and these heavy metal resistant bacteria can be useful for the bioremediation of heavy metal contaminated environment. </p>


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Muhammad Fauzul Imron ◽  
Setyo Budi Kurniawan ◽  
Siti Rozaimah Sheikh Abdullah

AbstractLeachate is produced from sanitary landfills containing various pollutants, including heavy metals. This study aimed to determine the resistance of bacteria isolated from non-active sanitary landfill leachate to various heavy metals and the effect of salinity levels on the removal of Hg by the isolated bacterium. Four dominant bacteria from approximately 33 × 1017 colony-forming units per mL identified as Vibrio damsela, Pseudomonas aeruginosa, Pseudomonas stutzeri, and Pseudomonas fluorescens were isolated from non-active sanitary landfill leachate. Heavy metal resistance test was conducted for Hg, Cd, Pb, Mg, Zn, Fe, Mn, and Cu (0–20 mg L− 1). The removal of the most toxic heavy metals by the most resistant bacteria was also determined at different salinity levels, i.e., fresh water (0‰), marginal water (10‰), brackish water (20‰), and saline water (30‰). Results showed that the growth of these bacteria is promoted by Fe, Mn, and Cu, but inhibited by Hg, Cd, Pb, Mg, and Zn. The minimum inhibitory concentration (MIC) of all the bacteria in Fe, Mn, and Cu was > 20 mg L− 1. The MIC of V. damsela was 5 mg L− 1 for Hg and >  20 mg L− 1 for Cd, Pb, Mg, and Zn. For P. aeruginosa, MIC was > 20 mg L− 1 for Cd, Pb, Mg, and Zn and 10 mg L− 1 for Hg. Meanwhile, the MIC of P. stutzeri was > 20 mg L− 1 for Pb, Mg, and Zn and 5 mg L− 1 for Hg and Cd. The MIC of P. fluorescens for Hg, Pb, Mg, and Zn was 5, 5, 15, and 20 mg L− 1, respectively, and that for Cd was > 20 mg L− 1. From the MIC results, Hg is the most toxic heavy metal. In marginal water (10‰), P. aeruginosa FZ-2 removed up to 99.7% Hg compared with that in fresh water (0‰), where it removed only 54% for 72 h. Hence, P. aeruginosa FZ-2 is the most resistant to heavy metals, and saline condition exerts a positive effect on bacteria in removing Hg.


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1530
Author(s):  
Amanuel Balemi ◽  
Balako Gumi ◽  
Kebede Amenu ◽  
Sisay Girma ◽  
Muuz Gebru ◽  
...  

A study was carried out from August 2017 to February 2018 on lactating dairy cows, one-humped dromedary camels, and goats to determine mastitis in the Bule Hora and Dugda Dawa districts of in Southern Ethiopia. Milk samples from 564 udder quarters and udder halves from 171 animals consisting of 60 dairy cows, 51 camels, and 60 goats were tested for mastitis. Sixty-four positive udder milk samples were cultured, and bacterial mastitis pathogens were isolated and identified. The antibiotic resistance of bacterial isolates from milk with mastitis was tested against nine antimicrobials commonly used in the study area. Cow- and quarter-level prevalence of mastitis in dairy cows, camels, and goats was 33.3%, 26.3%, and 25% and 17.6%, 14.5%, and 20%, respectively. In cattle, the prevalence was significantly higher in Dugda Dawa than in Bule Hora. Major bacterial isolates were coagulase-negative Staphylococcus species (39.1%), S. aureus (17.2%), S. hyicus (14.1%), and S. intermedius and Escherichia coli (9.4% each). In camels, udder abnormality and mastitis were significantly higher in late lactation than in early lactation. Mastitis tends to increase with parity in camels. E. coli isolates were highly resistant to spectinomycin, vancomycin, and doxycycline, whereas most S. aureus isolates were multidrug-resistant. Most of the rural and periurban communities in this area consume raw milk, which indicates a high risk of infection with multidrug-resistant bacteria. We recommend a community-focused training program to improve community awareness of the need to boil milk and the risk of raw milk consumption.


Author(s):  
Khansa Rahman ◽  
Unnikrishna Menon ◽  
Sivasubramanian V ◽  
Ranjitha J

2018 ◽  
Vol 7 (1) ◽  
pp. 28-40
Author(s):  
Bikram Gautam ◽  
Rameshwar Adhikari

Wastewater treatment plant is a potential reservoir contributing to the evolution and spread of heavy metal and antibiotic resistant bacteria. The pollutants such as biocides, antibiotics, heavy metals are to be feared for as they have been known to evoke resistance in microorganisms in such polluted environment. The aim of this study was to the isolate bacteria from the treated wastewater and assess the resistance pattern of the isolates against antibiotics and heavy metals. Grab sampling was performed from April to June 2017, from the treated effluent from the secondary treatment plant. To assess the resistance pattern for antibiotic(s) and heavy metal(s), antibiotic susceptibility test and minimum inhibitory concentration by cup well method were performed respectively. Staphylococcus aureus, Enterococcus faecalis, Citrobacter freundii, Escherichia coli, Enterobacter aerogenes, Proteus mirabilis, P. vulgaris, Salmonella Typhi, Pseudomonas aeruginosa were isolated. Multi drug and heavy metal resistant isolates were screened. Fisher’s exact test revealed that there is a significant association (p< 0.001) between antibiotic resistance pattern and resistance patterns at dilution of 2500 g/L (25%). Cramer’s V test revealed that the effect size of antibiotic resistance pattern and heavy metal resistance pattern at dilution 2500 g/L is medium. P. aeruginosa was able to resist the metal concentration up to 10000 g/L (100%) dilution of Fe++. Heavy metal resistant bacteria can be safely used to lower chemical concentration in the environment once their harmful genes are edited, knocked etc. so that risks of evoking antibiotic resistance could be minimized. 


1980 ◽  
Vol 1 (06) ◽  
pp. 391-400 ◽  
Author(s):  
Donald A. Goldmann ◽  
Ann B. Macone

This article details the appropriate microbiologic support that is critical to the successful investigation of nosocomial infection problems. The infection control team must have ready access to microbiologic data, and the laboratory should retain epidemiologically relevant bacterial isolates. Investigation of epidemics is facilitated by precise identification of bacteria and careful antibiotic susceptibility testing. In some situations, biotyping, serotyping, phage typing, bacteriocin typing, and other specialized techniques may be required. Plasmid analysis may be useful in the investigation of nosocomial infection problems caused by antibiotic-resistant bacteria.


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