scholarly journals Widespread Utilization of Diverse Organophosphate Pollutants by Marine Bacteria

2021 ◽  
Author(s):  
Dragana Despotovic ◽  
Einav Aharon ◽  
Olena Trofimyuk ◽  
Artem Dubovetskyi ◽  
Kesava Phaneendra Cherukuri ◽  
...  

Anthropogenic organophosphates (AOPs), such as phosphotriesters, are used extensively as plasticizers, flame retardants, nerve agents and pesticides. Soil bacteria bearing a phosphotriesterase (PTE) can degrade AOPs, but whether bacteria are capable of utilizing AOPs as a phosphorus source, and how widespread PTEs are in nature, remains unclear. Here, we report the utilization of diverse AOPs by four model marine bacteria and seventeen bacterial isolates from seawater samples. To unravel the details of AOP utilization, two novel PTEs from marine bacteria were isolated and characterized. When expressed in E. coli, these PTEs enabled growth on a pesticide analog as the sole phosphorus source. Utilization of AOPs provides bacteria with a source of phosphorus in depleted environments and offers a new prospect for the bioremediation of a pervasive class of anthropogenic pollutants.

2020 ◽  
Vol 36 (4) ◽  
pp. 126-135
Author(s):  
T.V. Shushkova ◽  
D.O. Epiktetov ◽  
S.V. Tarlachkov ◽  
I.T. Ermakova ◽  
A.A. Leontievskii

The degradation of persistent organophosphorus pollutants have been studied in 6 soil bacterial isolates and in 3 bacterial strains adapted for utilization of glyphosate herbicide (GP) under laboratory conditions. Significant differences in the uptake of organophosphonates were found in taxonomically close strains possessing similar enzymatic pathways of catabolism of these compounds, which indicates the existence of unknown mechanisms of activity regulation of these enzymes. The effect of adaptation for GP utilization as a sole phosphorus source on assimilation rates of several other phosphonates was observed in studied bacteria. The newly found efficient stains provided up to 56% of GP decomposition after application to the soil in the laboratory. The unresolved problems of microbial GP metabolism and the trends for further research on the creation of reliable biologicals capable of decomposing organophosphonates in the environment are discussed. organophosphonates, glyphosate, biodegradation, bioremediation, C-P lyase, phosphonatase, degrading bacteria Investigation of phosphonatase and genome sequencing were supported by Russian Science Foundation Grant no. 18-074-00021.


2019 ◽  
Vol 70 (5) ◽  
pp. 1778-1783
Author(s):  
Andreea-Loredana Golli ◽  
Floarea Mimi Nitu ◽  
Maria Balasoiu ◽  
Marina Alina Lungu ◽  
Cristiana Cerasella Dragomirescu ◽  
...  

To determine the resistance pattern of bacterial pathogens involved in infections of the patients aged between 18-64 years, admitted in a ICU from a 1518-bed university-affiliated hospital. A retrospective study of bacterial pathogens was carried out on 351 patients aged between 18-64 years admitted to the ICU, from January to December 2017. In this study there were analysed 469 samples from 351 patients (18-64 years). A total of 566 bacterial isolates were obtained, of which 120 strains of Klebsiella spp. (35.39%%), followed by Nonfermenting Gram negative bacilli, other than Pseudomonas and Acinetobacter (NFB) (75- 22.12%), Acinetobacter spp. (53 - 15.63%), Pseudomonas aeruginosa and Proteus (51 - 15.04%), and Escherichia coli (49 - 14.45%). The most common isolates were from respiratory tract (394 isolates � 69.61%). High rates of MDR were found for Pseudomonas aeruginosa (64.70%), MRSA (62.65%) and Klebsiella spp. (53.33%), while almost all of the isolated NFB strains were MDR (97.33%). There was statistic difference between the drug resistance rate of Klebsiella and E. coli strains to ceftazidime and ceftriaxone (p[0.001), cefuroxime (p[0.01) and to cefepime (p[0.01). The study revealed an alarming pattern of antibiotic resistance in the majority of ICU isolates.


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.


2010 ◽  
Vol 54 (11) ◽  
pp. 4684-4693 ◽  
Author(s):  
George G. Zhanel ◽  
Melanie DeCorby ◽  
Heather Adam ◽  
Michael R. Mulvey ◽  
Melissa McCracken ◽  
...  

ABSTRACT A total of 5,282 bacterial isolates obtained between 1 January and 31 December 31 2008, inclusive, from patients in 10 hospitals across Canada as part of the Canadian Ward Surveillance Study (CANWARD 2008) underwent susceptibility testing. The 10 most common organisms, representing 78.8% of all clinical specimens, were as follows: Escherichia coli (21.4%), methicillin-susceptible Staphylococcus aureus (MSSA; 13.9%), Streptococcus pneumoniae (10.3%), Pseudomonas aeruginosa (7.1%), Klebsiella pneumoniae (6.0%), coagulase-negative staphylococci/Staphylococcus epidermidis (5.4%), methicillin-resistant S. aureus (MRSA; 5.1%), Haemophilus influenzae (4.1%), Enterococcus spp. (3.3%), Enterobacter cloacae (2.2%). MRSA comprised 27.0% (272/1,007) of all S. aureus isolates (genotypically, 68.8% of MRSA were health care associated [HA-MRSA] and 27.6% were community associated [CA-MRSA]). Extended-spectrum β-lactamase (ESBL)-producing E. coli occurred in 4.9% of E. coli isolates. The CTX-M type was the predominant ESBL, with CTX-M-15 the most prevalent genotype. MRSA demonstrated no resistance to ceftobiprole, daptomycin, linezolid, telavancin, tigecycline, or vancomycin (0.4% intermediate intermediate resistance). E. coli demonstrated no resistance to ertapenem, meropenem, or tigecycline. Resistance rates with P. aeruginosa were as follows: colistin (polymyxin E), 0.8%; amikacin, 3.5%; cefepime, 7.2%; gentamicin, 12.3%; fluoroquinolones, 19.0 to 24.1%; meropenem, 5.6%; piperacillin-tazobactam, 8.0%. A multidrug-resistant (MDR) phenotype occurred frequently in P. aeruginosa (5.9%) but uncommonly in E. coli (1.2%) and K. pneumoniae (0.9%). In conclusion, E. coli, S. aureus (MSSA and MRSA), P. aeruginosa, S. pneumoniae, K. pneumoniae, H. influenzae, and Enterococcus spp. are the most common isolates recovered from clinical specimens in Canadian hospitals. The prevalence of MRSA was 27.0% (of which genotypically 27.6% were CA-MRSA), while ESBL-producing E. coli occurred in 4.9% of isolates. An MDR phenotype was common in P. aeruginosa.


2021 ◽  
Vol 3 (8) ◽  
Author(s):  
Muhammad Yasir ◽  
Basit Zeshan ◽  
Nur Hardy A. Daud ◽  
Izzah Shahid ◽  
Hafza Khalid

Abstract There is a need for more efficient and eco-friendly approaches to overcome increasing microbial infections. Bacteriocins and chitinases from Bacillus spp. can be powerful alternatives to conventional antibiotics and antifungal drugs, respectively. The purpose of this study was to assess the inhibitory potential of bacteriocins and chitinase enzymes against multiple resistant bacterial and fungal pathogens. Bacterial isolates were selected by growth on minimal salts medium and after that were morphologically and biochemically characterized. The physiochemical characterization of bacteriocins was carried out. The inhibitory potential of bacteriocins towards six pathogenic bacteria was determined by the well diffusion assay while chitinase activity towards three fungal strains was determined by the dual plate culture assay. Two bacterial strains (WW2P1 and WRE4P2), out of nine showed inhibition of K. pneumonia, P. aeruginosa, E. coli and MRSA while WW4P2 was positive against S. typhimurium and E. coli and WRE10P2 against P. aeruginosa, S. pneumoniae. Two bacterial isolates (WW3P1 and WRE10P2) were chosen for further study on the basis of their antifungal activities. Of these, WW3P1 isolate was more effective against A. fumigatus as well as A. niger. The proteinaceous nature of the bacteriocins was confirmed by treatment of the crude extract with proteinase K. It was found that the inhibitory activity of strain WW3P1 against E. coli was highest at 20 °C, and against S. pneumoniae it was at 20 °C and pH 10 after treatment with EDTA. Inhibition by strain the WRE10P2 against P. aeruginosa was highest at 20 °C and pH 14. It was found that EDTA increased the inhibitory activity of strain WW2P1 against P. aeruginosa, K. pneumoniae and E. coli by 2 ± 0.235, 3.5 ± 0.288, 2.5 ± 1.040 times, respectively, of strain WRE4P2 against P. aeruginosa and E. coli by 2.5 ± 0.763, 2.7 ± 0.5 times, respectively, and of strain WRE10P2 against S. pneumoniae by 3 ± 0.6236 times. The isolates have promising inhibitory activity, which should be further analyzed for the commercial production of antimicrobials. Article highlights The current study aimed to isolate the microbiome from wheat plant (Triticum aestivum L.), to screen for bacteriocin production and to assess its antimicrobial activity against human pathogens. Forty-one phenotypically different bacterial colonies were subjected to bacteriocin purification from which 25 colonies showed positive reactions. These 25 bacterial isolates were screened against six different human bacterial pathogens using the well diffusion method to check the antimicrobial activity. Out of nine bacterial isolates, WW3P1 and WRE10P2 were able to degrade the chitin and utilize it as their sole energy source. Strain WRE4P2 exhibited partial inactivation in its activity against MRSA after treatment with proteinase K.


Author(s):  
Kavi Aniis ◽  
Rajamanikandan Kcp ◽  
Arvind Prasanth D

<p>ABSTRACT<br />Objective: Beta-lactams are the group of antibiotics that contain a ring called as “beta-lactam ring,” which is responsible for the antibacterial activity.<br />The presence of resistance among Gram-negative organisms is due to the production of beta-lactamases enzymes that hydrolysis the beta-lactam ring<br />thereby conferring resistance to the organism. This study is undertaken to determine the prevalence of extended-spectrum beta-lactamase (ESBL)<br />producing Gram-negative organism from clinical samples.<br />Methods: A total of 112 clinical samples were taken for this study. The combined disc synergistic test (CDST) was used for the phenotypic detection<br />of ESBL producers from the clinical samples. The genotypic identification of ESBL producers was carried out by alkaline lysis method by isolation of<br />plasmid DNA.<br />Result: A total of 87 bacterial isolates were isolated and identified. Among them, Klebsiella (41%) was the predominant organism followed by<br />Escherichia coli (33%), Proteus (10%), Pseudomonas (10%), and Serratia (6%). Among the various bacterial isolates, Klebsiella showed a higher<br />percentage of resistance. The CDST showed that 8 isolates of Klebsiella, 3 isolates of E. coli, and 1 isolate of Pseudomonas were found to be ESBL<br />producers. The genotypic confirmation showed that the two bacterial isolates, namely, Klebsiella and E. coli were found to possess temoniera (TEM)<br />gene which was the 400-500 bp conferring resistance to the antibiotics.<br />Conclusion: The results of this study suggest that early detection of ESBL producing Gram-negative organism is a very important step in planning the<br />therapy of patient in Hospitals. CDST continues to be a good indicator in the detection of ESBL producers.<br />Keywords: Beta-lactamases, Gram-negative bacilli, Extended-spectrum beta-lactamase, Resistance, Combined disc synergistic test.</p><p> </p>


2021 ◽  
Vol 17 (2) ◽  
pp. 189-195
Author(s):  
TR Setyawati ◽  
AH Yanti ◽  
R. Kurniatuhadi

The bacterial isolates NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolated from fecal pellets and gastrointestinal tract of nypha worms (Namalycastis rhodochorde) have cellulolytic, proteolytic activity and produce organic acids. The four isolates have the potency to be developed as probiotics in nypha worm cultivation feed. This study aims to determine the probiotics potency and identify the species of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolate based on 16srDNA sequence. The probiotic potency was carried out by the acid tolerance assays on distilled water and 0.3% acid bile media, and the antimicrobial testing against Escherichia coli (MF exp21.12). Bacterial identification was carried out by sequencing of 16sDNA sequence based on GeneBank data. The results showed that the bacterial isolates of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were able to grow on 0.3% distilled water and acid bile media. However, only the NrLtF4 and NrLtF5 inhibited E. coli (MF exp21.12) with halo zones 30 mm and 18 mm, respectively. Blasting results of the 16srDNA sequences showed that the NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were closely related to Bacillus wiedmannii, Brevibacterium sediminis, Bacillus proteolyticus, and Bacillus paramycoides. The nypha worm bacterial isolates have the potency to be developed as probiotics in nypha worm culture.


2014 ◽  
Author(s):  
Jason W Sahl ◽  
Greg Caporaso ◽  
David A Rasko ◽  
Paul S Keim

Background. As whole genome sequence data from bacterial isolates becomes cheaper to generate, computational methods are needed to correlate sequence data with biological observations. Here we present the large-scale BLAST score ratio (LS-BSR) pipeline, which rapidly compares the genetic content of hundreds to thousands of bacterial genomes, and returns a matrix that describes the relatedness of all coding sequences (CDSs) in all genomes surveyed. This matrix can be easily parsed in order to identify genetic relationships between bacterial genomes. Although pipelines have been published that group peptides by sequence similarity, no other software performs the large-scale, flexible, full-genome comparative analyses carried out by LS-BSR. Results. To demonstrate the utility of the method, the LS-BSR pipeline was tested on 96 Escherichia coli and Shigella genomes; the pipeline ran in 163 minutes using 16 processors, which is a greater than 7-fold speedup compared to using a single processor. The BSR values for each CDS, which indicate a relative level of relatedness, were then mapped to each genome on an independent core genome single nucleotide polymorphism (SNP) based phylogeny. Comparisons were then used to identify clade specific CDS markers and validate the LS-BSR pipeline based on molecular markers that delineate between classical E. coli pathogenic variant (pathovar) designations. Scalability tests demonstrated that the LS-BSR pipeline can process 1,000 E. coli genomes in ~60h using 16 processors. Conclusions. LS-BSR is an open-source, parallel implementation of the BSR algorithm, enabling rapid comparison of the genetic content of large numbers of genomes. The results of the pipeline can be used to identify specific markers between user-defined phylogenetic groups, and to identify the loss and/or acquisition of genetic information between bacterial isolates. Taxa-specific genetic markers can then be translated into clinical diagnostics, or can be used to identify broadly conserved putative therapeutic candidates.


Author(s):  
Sneha S ◽  
Mrunal Palsokar ◽  
Vemula Sai Jahnavi ◽  
Anwesha Sarkar ◽  
K. V. Bhaskara Rao

Protease constitutes the major group of catalytic enzymes which is involved in hydrolyzing peptide bond of proteins. Marine sediment sample were collected and protease producing bacterial isolates were identified by using casein as a substrate. The organisms were characterized by biochemical test and identified as Bacillus sp. In order to check for the production of protease enzyme, quantitative protease assay and Lowry’s method of protein estimation was carried out. The crude extract of protease was subjected for blood stain removal activity and the enzyme proved to be efficient which removed the stain in 15 min. The purpose of the current study is to isolate, identify, characterize and to carry out applications of protease enzyme from marine bacteria isolated from mangrove sediment samples.


Author(s):  
Yang Yu ◽  
Jie Yang ◽  
Zhao-Jie Teng ◽  
Li-Yuan Zheng ◽  
Qi Sheng ◽  
...  

As the most abundant D-amino acid (DAA) in the ocean, D-alanine (D-Ala) is a key component of peptidoglycan in bacterial cell wall. However, the underlying mechanisms of bacterial metabolization of D-Ala through microbial food web remain largely unknown. In this study, the metabolism of D-Ala by marine bacterium Pseudoalteromonas sp. CF6-2 was investigated. Based on genomic, transcriptional and biochemical analyses combined with gene knockout, D-Ala aminotransferase was found to be indispensable for the catabolism of D-Ala in strain CF6-2. Investigation on other marine bacteria also showed that D-Ala aminotransferase gene is a reliable indicator for their ability to utilize D-Ala. Bioinformatic investigation revealed that D-Ala aminotransferase sequences are prevalent in genomes of marine bacteria and metagenomes, especially in seawater samples, and Gammaproteobacteria represents the predominant group containing D-Ala aminotransferase. Thus, Gammaproteobacteria is likely the dominant group to utilize D-Ala via D-Ala aminotransferase to drive the recycling and mineralization of D-Ala in the ocean. IMPORTANCE As the most abundant D-amino acid in the ocean, D-Ala is a component of marine DON (Dissolved organic nitrogen) pool. However, the underlying mechanism of bacterial metabolization of D-Ala to drive the recycling and mineralization of D-Ala in the ocean is still largely unknown. The results in this study showed that D-Ala aminotransferase is specific and indispensable for D-Ala catabolism in marine bacteria, and that marine bacteria containing D-Ala aminotransferase genes are predominantly Gammaproteobacteria widely distributed in global oceans. This study reveals marine D-Ala utilizing bacteria and the mechanism of their metabolization of D-Ala. The results shed light on the mechanisms of recycling and mineralization of D-Ala driven by bacteria in the ocean, which are helpful in understanding oceanic microbial-mediated nitrogen cycle.


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