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Brazilian Journal of Microbiology :... Apr 2008Sarcophagidae) are well known cause of myiasis and their gut bacteria have never been studied for antimicrobial activity against bacteria. Antimicrobial studies of...
Antibacterial activities of multi drug resistant Myroides odoratimimus bacteria isolated from adult flesh flies (Diptera: sarcophagidae) are independent of metallo beta-lactamase gene.
Sarcophagidae) are well known cause of myiasis and their gut bacteria have never been studied for antimicrobial activity against bacteria. Antimicrobial studies of Myroides spp. are restricted to nosocomial strains. A Gram-negative bacterium, Myroides sp., was isolated from the gut of adult flesh flies (Sarcophaga sp.) and submitted to evaluation of nutritional parameters using Biolog GN, 16S rRNA gene sequencing, susceptibility to various antimicrobials by disc diffusion method and detection of metallo β-lactamase genes (TUS/MUS). The antagonistic effects were tested on Gram-negative and Gram-positive bacteria isolated from human clinical specimens, environmental samples and insect mid gut. Bacterial species included were Aeromonas hydrophila, A. culicicola, Morganella morganii subsp. sibonii, Ochrobactrum anthropi, Weissella confusa, Escherichia coli, Ochrobactrum sp., Serratia sp., Kestersia sp., Ignatzschineria sp., Bacillus sp. The Myroides sp. strain was resistant to penicillin-G, erythromycin, streptomycin, amikacin, kanamycin, gentamycin, ampicillin, trimethoprim and tobramycin. These strain showed antibacterial action against all bacterial strains except W. confusa, Ignatzschineria sp., A. hydrophila and M. morganii subsp. sibonii. The multidrug resistance of the strain was similar to the resistance of clinical isolates, inhibiting growth of bacteria from clinical, environmental and insect gut samples. The metallo β-lactamase (TUS/MUS) genes were absent, and resistance due to these genes was ruled out, indicating involvement of other secretion machinery.
PubMed: 24031236
DOI: 10.1590/S1517-838220080002000035 -
Molecules (Basel, Switzerland) Jun 2015The protease myroilysin is the most abundant protease secreted by marine sedimental bacterium Myroides profundi D25. As a novel elastase of the M12 family, myroilysin...
The protease myroilysin is the most abundant protease secreted by marine sedimental bacterium Myroides profundi D25. As a novel elastase of the M12 family, myroilysin has high elastin-degrading activity and strong collagen-swelling ability, suggesting its promising biotechnological potential. Because myroilysin cannot be maturely expressed in Escherichia coli, it is important to be able to improve the production of myroilysin in the wild strain D25. We optimized the culture conditions of strain D25 for protease production by using single factor experiments. Under the optimized conditions, the protease activity of strain D25 reached 1137 ± 53.29 U/mL, i.e., 174% of that before optimization (652 ± 23.78 U/mL). We then conducted small scale fermentations of D25 in a 7.5 L fermentor. The protease activity of strain D25 in small scale fermentations reached 1546.4 ± 82.65 U/mL after parameter optimization. Based on the small scale fermentation results, we further conducted pilot scale fermentations of D25 in a 200 L fermentor, in which the protease production of D25 reached approximately 1100 U/mL. These results indicate that we successfully set up the small and pilot scale fermentation processes of strain D25 for myroilysin production, which should be helpful for the industrial production of myroilysin and the development of its biotechnological potential.
Topics: Bacteroides; Culture Media; Fermentation; Marine Biology; Metalloproteases; Nitrogen; Pilot Projects; Temperature
PubMed: 26132910
DOI: 10.3390/molecules200711891 -
Case Reports in Infectious Diseases 2023is a Gram-negative opportunistic pathogen known to rarely cause a wide range of opportunistic infections in humans. We report a novel case of bacteremia in a...
is a Gram-negative opportunistic pathogen known to rarely cause a wide range of opportunistic infections in humans. We report a novel case of bacteremia in a paraplegic patient with an extensive medical history likely due to a tunneled dialysis catheter infection that was successfully treated with levofloxacin.
PubMed: 38020519
DOI: 10.1155/2023/3089837 -
Antimicrobial Agents and Chemotherapy Dec 1997Several Flavobacterium species, comprising a heterogeneous group of gram-negative bacilli that are capable of causing opportunistic infections in humans, have recently...
Several Flavobacterium species, comprising a heterogeneous group of gram-negative bacilli that are capable of causing opportunistic infections in humans, have recently been reclassified as Chryseobacterium or Myroides species. Intrinsically resistant to a number of antibiotics, these organisms have been reported to be susceptible to vancomycin and certain other drugs that are normally active against gram-positive bacteria. By using the National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution procedure, 58 clinical isolates of former flavobacteria (36 Chryseobacterium meningosepticum isolates, 11 C. indologenes isolates, 3 C. gleum isolates, 4 unspeciated former members of Flavobacterium group IIb, and 4 Myroides odoratum isolates) were tested with 23 antibiotics, including conventional and investigational agents. In addition, the broth microdilution results were compared to those generated by agar dilution, E-test, and disk diffusion for vancomycin and piperacillin-tazobactam. Compared to the NCCLS microdilution results, there were 7.1 and 17.9% very major errors with piperacillin-tazobactam by agar dilution and E-test, respectively. In addition, there were from 12.1 to 48.3% minor errors with both procedures with vancomycin and piperacillin-tazobactam. The very major and minor error rates were unacceptably high with disk testing of piperacillin-tazobactam; the use of enterococcal vancomycin disk breakpoints (zone diameter of > or =17 mm = susceptible) resulted in >20% minor errors but only one very major error. All of the isolates were susceptible to minocycline; over 90% were susceptible to sparfloxacin, levofloxacin, and clinafloxacin; and 88% were susceptible to rifampin. None was susceptible to vancomycin. When Chryseobacterium or Myroides species are isolated from serious infections, susceptibility testing by broth microdilution should be performed and therapy should be guided by those results.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Drug Therapy, Combination; Flavobacterium; Fluoroquinolones; Microbial Sensitivity Tests; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Reproducibility of Results; Vancomycin
PubMed: 9420049
DOI: 10.1128/AAC.41.12.2738 -
Ecotoxicology and Environmental Safety Jan 2024Thiram, a typical fungicide pesticide, is widely used in agricultural production. The presence of thiram residues is not only due to over-utilization, but is also...
Thiram, a typical fungicide pesticide, is widely used in agricultural production. The presence of thiram residues is not only due to over-utilization, but is also primarily attributed to long-term accumulation. However, there is a paucity of information regarding the impact of prolonged utilization of thiram at low doses on the gut microbiota, particularly with respect to gut fungi. Our objective is to explore the effect of thiram on broilers from the perspective of gut microbiota, which includes both bacteria and fungi. We developed a long-term low-dose thiram model to simulate thiram residue and employed 16 S rRNA and ITS gene sequencing to investigate the diversity and profile of gut microbiota between group CC (normal diet) and TC (normal diet supplemented with 5 mg/kg thiram). The results revealed that low doses of thiram had a detrimental effect on broiler's growth performance, resulting in an approximate reduction of 669.33 g in their final body weight at day 45. Our findings indicated that low-dose thiram had a negative impact on the gut bacterial composition, leading to a notable reduction in the abundance of Merdibacter, Paenibacillus, Macrococcus, Fournierella, and Anaeroplasma (p < 0.05) compared to the CC group. Conversely, the relative level of Myroides was significantly increased (p < 0.05) in response to thiram exposure. In gut fungi, thiram significantly enhanced the diversity and richness of gut fungal populations (p < 0.05), as evidenced by the notable increase in alpha indices, i.e. ACE (CC: 346.49 ± 117.27 vs TC: 787.27 ± 379.14, p < 0.05), Chao 1 (CC: 317.63 ± 69.13 vs TC: 504.85 ± 104.50, p < 0.05), Shannon (CC: 1.28 ± 1.19 vs TC: 5.39 ± 2.66, p < 0.05), Simpson (CC: 0.21 ± 0.21 vs TC: 0.78 ± 0.34, p < 0.05). Furthermore, the abundance of Ascomycota, Kickxellomycota, and Glomeromycota were significantly increased (p < 0.05) by exposure to thiram, conversely, the level of Basidiomycota was decreased (p < 0.05) in the TC group compared to the CC group. Overall, this study demonstrated that low doses of thiram induced significant changes in the composition and abundance of gut microbiota in broilers, with more pronounced changes observed in the gut fungal community as compared to the gut bacterial community. Importantly, our findings further emphasize the potential risks associated with low dose thiram exposure and have revealed a novel discovery indicating that significant alterations in gut fungi may serve as the crucial factor contributing to the detrimental effects exerted by thiram residues.
Topics: Animals; Thiram; Chickens; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Fungicides, Industrial; Bacteria
PubMed: 38157796
DOI: 10.1016/j.ecoenv.2023.115879 -
Avicenna Journal of Medical... 2019The present study focused on the production of L-asparaginase using Solid State Fermentation (SSF) by
BACKGROUND
The present study focused on the production of L-asparaginase using Solid State Fermentation (SSF) by
METHODS
Initially, five significant parameters (Carbon source; Nitrogen source, temperature, pH and incubation period) were identified that affect the production process of L-asparaginase using Classical One Factor at a Time (OFAT) optimization. An optimized L-asparaginase specific activity obtained by OFAT was recorded as 85.7 . Central Composite Design (CCD) was also employed successively to optimize the multiple parameters at a time and their results were compared.
RESULTS
Maximum L-asparaginase enzyme specific activity obtained by CCD method was 295.6 under the hold values of carbon source (wheat bran) 12 , nitrogen source (yeast extract) 7 , temperature 37°, pH=7.5 and incubation period 47 . Upon validation, the obtained results proved that there was a good relation existing between the experimental and the predicted model (p<0.05). L-asparaginase activity was enhanced in statistical method up to 3.4 folds compared to that of classical method.
CONCLUSION
Utilization of wheat bran as a low cost carbon source in SSF for the production of L-asparaginase enzyme makes the process economical and in turn reduces the environmental pollution by biotransformation to commercially useful bio product.
PubMed: 30800244
DOI: No ID Found -
Journal of Applied Microbiology Mar 1998Eighty-five catalase- and oxidase-positive Gram-negative rods and cocci susceptible to penicillin G were isolated from a variety of food sources. The phenotypic... (Comparative Study)
Comparative Study
Eighty-five catalase- and oxidase-positive Gram-negative rods and cocci susceptible to penicillin G were isolated from a variety of food sources. The phenotypic relationships of these isolates with reference cultures of Bergeyella-like, Chryseobacterium, Empedobacter, Myroides, Moraxella, Sphingobacterium and Weeksella-like strains were examined by numerical taxonomy. Seventy-three isolates were recovered in five groups; 80% of the isolates clustered in groups 1, 2 and 3 and produced indole, bearing a strong resemblance to Weeksella and Bergeyella. They could not, however, be regarded as belonging to the known species of W. virosa and B. zoohelcum. It is suggested that three species may be necessary to accommodate the environmental Weeksella- or Bergeyella-like bacteria. The isolates in groups 4 and 5 had white colonies and were unable to produce indole, in this way resembling the Moraxella genus.
Topics: Bacterial Typing Techniques; Food Microbiology; Gram-Negative Aerobic Rods and Cocci; Gram-Negative Bacteria; Moraxella
PubMed: 9721639
DOI: 10.1046/j.1365-2672.1998.00346.x -
Xenotransplantation 2015The longest survival of a non-human primate with a life-supporting kidney graft to date has been 90 days, although graft survival > 30 days has been unusual. A baboon...
The longest survival of a non-human primate with a life-supporting kidney graft to date has been 90 days, although graft survival > 30 days has been unusual. A baboon received a kidney graft from an α-1,3-galactosyltransferase gene-knockout pig transgenic for two human complement-regulatory proteins and three human coagulation-regulatory proteins (although only one was expressed in the kidney). Immunosuppressive therapy was with ATG+anti-CD20mAb (induction) and anti-CD40mAb+rapamycin+corticosteroids (maintenance). Anti-TNF-α and anti-IL-6R were administered. The baboon survived 136 days with a generally stable serum creatinine (0.6 to 1.6 mg/dl) until termination. No features of a consumptive coagulopathy (e.g., thrombocytopenia, decreased fibrinogen) or of a protein-losing nephropathy were observed. There was no evidence of an elicited anti-pig antibody response. Death was from septic shock (Myroides spp). Histology of a biopsy on day 103 was normal, but by day 136, the kidney showed features of glomerular enlargement, thrombi, and mesangial expansion. The combination of (i) a graft from a specific genetically engineered pig, (ii) an effective immunosuppressive regimen, and (iii) anti-inflammatory agents prevented immune injury and a protein-losing nephropathy, and delayed coagulation dysfunction. This outcome encourages us that clinical renal xenotransplantation may become a reality.
Topics: Animals; Animals, Genetically Modified; Antigens, Heterophile; Complement System Proteins; Galactosyltransferases; Gene Knockout Techniques; Genetic Engineering; Graft Survival; Humans; Immunosuppressive Agents; Kidney; Kidney Transplantation; Papio; Swine; Time Factors; Transplantation, Heterologous
PubMed: 26130164
DOI: 10.1111/xen.12174 -
Microbiology (Reading, England) Oct 2001Chryseobacterium meningosepticum is an aerobic Gram-negative rod widely distributed in natural environments. Unlike many bacteria, it produces a phosphate-irrepressible...
Chryseobacterium meningosepticum is an aerobic Gram-negative rod widely distributed in natural environments. Unlike many bacteria, it produces a phosphate-irrepressible periplasmic alkaline phosphatase (AP). This work describes cloning of the gene encoding that enzyme from C. meningosepticum CCUG 4310 (NCTC 10585), and preliminary characterization of its product. The gene, named pafA, encodes a protein (PafA) of 546 amino acids with a calculated molecular mass of the mature peptide of 58682 Da. PafA exhibits high sequence identity with the PhoV AP of Synechococcus PCC 7942 (49.9% identity) and with the Cda Ca(2+)-dependent ATPase of Myroides odoratus (51.9% identity), while being more distantly related to the PhoD AP of Zymomonas mobilis (22.1% identity) and to the PhoA AP of Escherichia coli (14.0% identity). PafA was partially purified; it exhibits optimal activity at pH 8.5 and is active towards a broad spectrum of substrates including both phosphomonoesters and ATP, with preferential activity for the latter compound. The present findings allow definition of a new family of APs including 60 kDa, periplasmic enzymes whose expression is not influenced by freely available P(i) in the medium. Moreover, PafA can be considered an evolutionary intermediate between Ca(2+)-ATPase of M. odoratus and the APs PhoV of Synechococcus PCC 7942 and PhoD of Z. mobilis.
Topics: Alkaline Phosphatase; Amino Acid Sequence; Bacterial Proteins; Cloning, Molecular; Enzyme Repression; Flavobacterium; Molecular Sequence Data; Periplasm; Phosphates; Phylogeny; Sequence Analysis, DNA
PubMed: 11577161
DOI: 10.1099/00221287-147-10-2831 -
Frontiers in Microbiology 2024Chinese cabbage, scientifically known as subsp is a highly popular vegetable in China for its delectable taste. However, the occurrence of bacterial soft rot disease...
Chinese cabbage, scientifically known as subsp is a highly popular vegetable in China for its delectable taste. However, the occurrence of bacterial soft rot disease poses a significant threat to its growth and overall development. Consequently, this study aimed to explore the defense mechanisms employed by Chinese cabbage against bacterial soft rot disease. Specifically, the investigation focused on understanding the relationship between the disease and the microbial communities present in the soil surrounding the roots of Chinese cabbage. Significant disparities were observed in the composition of microbial communities present in the root-zone soil of healthy Chinese cabbage plants compared to those affected by -caused soft rot disease. The analysis of 16S rRNA gene high-throughput sequencing results revealed a lower abundance of Proteobacteria (8.39%), Acidobacteriot (0.85), (3.51%), and (1.48%), whereas Firmicutes (113.76%), Bacteroidota (8.71%), Chloroflexi (4.89%), Actinobacteriota (1.71%), A4b (15.52%), (1.62%), and (1.35%) were more prevalent in healthy plant soils. Similarly, the analysis of ITS gene high-throughput sequencing results indicated a reduced occurrence of Chytridiomycota (23.58%), Basidiomycota (21.80%), (86.22%), and (22.57%) in healthy soils. In comparison, Mortierellomycota (50.72%), Ascomycota (31.22%), (485.08%), and (51.59%) were more abundant in healthy plant soils. In addition, a total of 15 bacterial strains were isolated from the root-zone soil of diseased Chinese cabbage plants. These isolated strains demonstrated the ability to fix nitrogen (with the exception of ZT20, ZT26, ZT41, ZT45, and ZT61), produce siderophores and indole acetic acid (IAA), and solubilize phosphate. Notably, ZT14 (), ZT33 (), ZT41 (), ZT52 (), ZT58 (), ZT45 (), and ZT32 () exhibited significant growth-promoting effects as determined by the plant growth promotion (PGP) tests. Consequently, this investigation not only confirmed the presence of the soft rot pathogen in Chinese cabbage plants in Hangzhou, China, but also advanced our understanding of the defense mechanisms employed by Chinese cabbage to combat soft rot-induced stress. Additionally, it identified promising plant-growth-promoting microbes (PGPMs) that could be utilized in the future to enhance the Chinese cabbage industry.
PubMed: 38784798
DOI: 10.3389/fmicb.2024.1401896