Search

Cadmium (Cd) is a highly toxic metal that frequently contaminates our environment. In this study, the bioflocculant-producing, cadmium-resistant Escherichia fergusonii ZSF-15 was characterized from Paharang drain, Bawa Chak, Faisalabad, Pakistan. The Cd-resistant E. fergusonii was used to determine the bioflocculant production using yeast-peptone-glycerol medium (pH 6.5) supplemented with 50 mg L−1 of Cd. The culture was incubated for 3 days at 37 °C in a rotary shaker at 120 rpm. The fermentation broth was centrifuged at 4000 g for 10 min after the incubation period. The maximum flocculating activity by isolate ZSF-15 was found to be 71.4% after 48 h of incubation. According to the Fourier transform infrared spectroscopy analysis, the bioflocculant produced by strain ZSF-15 was comprised of typical polysaccharide and protein, i.e. hydroxyl, carboxyl, and amino groups. The strain ZSF-15 exhibited bioflocculant activity at range of pH (6–8) and temperature (35–50℃). Maximum flocculation activity (i.e. 71%) was observed at 47℃, whereas 63% flocculation production was observed at pH 8. In the present study, antioxidant enzyme profile of ZSF-15 was also evaluated under cadmium stress. A significant increase in antioxidant enzymes including superoxide dismutase (118%) and ascorbate peroxidase (28%) was observed, whereas contents of catalase (86%), glutathione transferase (13%), and peroxidase (8%) were decreased as compared to control. [ABSTRACT FROM AUTHOR]

aima Muzammil,1 Mohsin Khurshid,1 Muhammad Hidayat Rasool,1 Moeed Ahmad,1 Tamoor Hamid Chaudhry,3 Afreenish Amir,3 Muhammad Salman,3 Zulqarnain Baloch,4 Norah A Alturki,5 Ahmad Alzamami61Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan; 2Department of Bioinformatics & Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan; 3Public Health Laboratories Division, National Institute of Health, Islamabad, Pakistan; 4Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, People's Republic of China; 5Clinical Laboratory Science Department, College of Applied Medical Science, King Saud University, Riyadh, Saudi Arabia; 6Clinical Laboratory Science Department, College of Applied Medical Science, Shaqra University, AlQuwayiyah, Saudi ArabiaCorrespondence: Bilal Aslam, Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan, Email [email protected] Ahmad Alzamami, Clinical Laboratory Science Department, College of Applied Medical Science, Shaqra University, AlQuwayiyah, Saudi Arabia, Email [email protected] Background: The World Health Organization (WHO) has declared the multi-drug resistant (MDR) Klebsiella pneumoniae as one of the critical bacterial pathogens. The dearth of new antibiotics and inadequate therapeutic options necessitate finding alternative options. Bacteriophages are known as enemies of bacteria and are well-recognized to fight MDR pathogens. Methods: A total of 150 samples were collected from different clinical specimens through a convenient sampling technique. Isolation, identification, and antibiotic susceptibility testing (AST) of K. pneumoniae were done by standard and validated microbiological procedures. Molecular identification of virulence factors and antibiotic resistance genes (ARGs) was carried out through polymerase chain reaction (PCR) by using specific primers. For bacteriophage isolation, hospital sewage samples were processed for phage enrichment, purification, and further characterization ie, transmission electron microscopy (TEM) and stability testing, etc. followed by evaluation of the lytic potential of the phage. Results: Overall, a total of 41% of isolates of K. pneumoniae were observed as hypervirulent K. pneumoniae (hvKp). Among hvKp, a total of 12 (42%) were detected as MDR hvKp. A total of 37% of all MDR isolates were found resistant to colistin, and 66% of the colistin resistance isolates were recorded as mcr-1 positive. Isolated phage KpnM had shown lytic activity against 53 (79%) K. pneumoniae isolates. Remarkably, all 8 mcr-1 harboring MDR hvKp and non-hvKp isolates were susceptible to KpnM phage. Conclusion: Significant distribution of mcr-1 harboring hypervirulent Klebsiella pneumoniae was observed in clinical specimens, which is worrisome for the health system of the country. Characterized phage KpnM exhibited encouraging results and showed the lytic activity against the mcr-1 harboring hvKp isolates, which may be used as a prospective alternative control strategy to fight this ominous bacterium. [ABSTRACT FROM AUTHOR]

aima Muzammil,2 Nafeesa Yasmeen,4 Muhammad Aamir Aslam,3 Mohsin Khurshid,2 Muhammad Hidayat Rasool,2 Zulqarnain Baloch11Biomedical Research Center, Northwest Minzu University, Lanzhou 730030, People's Republic of China; 2Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan; 3Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan; 4College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, People's Republic of ChinaCorrespondence: Bilal Aslam; Zulqarnain Baloch Email drbilalaslam@gcuf.edu.pk; znbalooch@yahoo.com Introduction: Intense livestock farming practices enforcing the farmers to use antibiotics as food supplements on a routine basis. Aberrant use of antibiotics is associated with the emergence of antibiotics resistance and resistant superbugs. Keeping in view the current scenario, the present study was designed for the first time from Pakistan with a specific aim to estimate the prevalence of the carbapenem-resistant Klebsiella pneumoniae in veterinary settings and the waste in Pakistan. Methods: A total of 138 samples from various veterinary sources were collected by employing a nonprobability sampling technique. Isolation and phenotypic identification of carbapenem-resistant K. pneumoniae were performed according to the CLSI standard. Molecular detection of various antibiotic resistance genes (ARGs) was done through PCR by using specific primers against each ARG. According to the pasture scheme, the multilocus sequence typing (MLST) was performed to characterize the K. pneumoniae sequence types (STs). Results: According to the results of the study, overall 9.4% (13/138) isolates were confirmed carbapenem-resistant K. pneumoniae. Among various carbapenem ARGs particularly, the blaNDM-1 was found in 92.3% (12/13) isolates followed by blaOXA-48 84.6% (11/13). MLST results revealed that overall 3 STs were found in the study which includes ST29, ST11, and ST258. Taking together, this is the first study to our best knowledge which demonstrated the prevalence of carbapenem-resistant K. pneumoniae and its various STs prevalent in veterinary settings and the waste of Pakistan. Conclusion: Based on the above-mentioned facts, we suggested that veterinary settings and waste are the potential source and reservoir of carbapenem-resistant K. pneumoniae, which may be disseminated to the environment and ultimately can affect the public and companion livestock health. [ABSTRACT FROM AUTHOR]