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Veterinary World Aug 2021The emergence of antibiotic-resistant bacterial pathogens has been increasingly reported, which has resulted in a decreasing ability to treat bacterial infections....
BACKGROUND AND AIM
The emergence of antibiotic-resistant bacterial pathogens has been increasingly reported, which has resulted in a decreasing ability to treat bacterial infections. Therefore, this study investigated the presence of spp., including its antibiotic resistance in various fish samples, spp., , and , obtained from Kelantan and Terengganu, Malaysia.
MATERIALS AND METHODS
In this study, 221 fish samples, of which 108 ( spp., n=38; , n=35; and , n=35) were from Kelantan and 113 ( spp., n=38; , n=35; and , n=40) were from Terengganu, were caught using cast nets. Then, samples from their kidneys were cultured on a Rimler Shott agar to isolate spp. Polymerase chain reaction (PCR) was used to confirm this isolation using specific gene primers for species identification. Subsequently, the isolates were tested for their sensitivity to 14 antibiotics using the Kirby-Bauer method, after which the PCR was conducted again to detect resistance genes: , -, , , , -, and .
RESULTS
From the results, 61 isolates were identified as being from the genus using PCR, of which 28 were , 19 were , seven were , and seven were . Moreover, 8, 12, and 8 of ; 4, 3, and 12 of ; 6, 0, and 1 of ; and 3, 3, and 1 of were obtained from spp., , and , respectively. In addition, the isolates showed the highest level of resistance to ampicillin (100%), followed by streptomycin (59.0%), each kanamycin and nalidixic acid (41.0%), neomycin (36.1%), tetracycline (19.7%), sulfamethoxazole (14.8%), and oxytetracycline (13.1%). Resistance to gentamicin and ciprofloxacin both had the same percentage (9.8%), whereas isolates showed the lowest resistance to norfloxacin (8.2%) and doxycycline (1.6%). Notably, all isolates were susceptible to chloramphenicol and nitrofurantoin. Results also revealed that the multiple antibiotic resistances index of the isolates ranged from 0.07 to 0.64, suggesting that the farmed fish in these areas were introduced to the logged antibiotics indiscriminately and constantly during their cultivation stages. Results also revealed that the gene was detected in 19.7% of the isolates, whereas the tetracycline resistance genes, and , were detected in 27.9% and 4.9% of the isolates, respectively. However, β-lactam resistance genes, and , were found in 44.3% and 13.1% of isolates, respectively, whereas and genes were found in 3.3% and 13.1% of the isolates, respectively.
CONCLUSION
This study, therefore, calls for continuous surveillance of antibiotic-resistant spp. in cultured freshwater fish to aid disease management and better understand their implications to public health.
PubMed: 34566322
DOI: 10.14202/vetworld.2021.2064-2072 -
Scientific Reports Mar 2021Diseased Anabas testudineus exhibiting signs of tail-rot and ulcerations on body were collected from a fish farm in Assam, India during the winter season (November 2018...
Diseased Anabas testudineus exhibiting signs of tail-rot and ulcerations on body were collected from a fish farm in Assam, India during the winter season (November 2018 to January 2019). Swabs from the infected body parts were streaked on sterilized nutrient agar. Two dominant bacterial colonies were obtained, which were then isolated and labelled as AM-31 and AM-05. Standard biochemical characterisation and 16S rRNA and rpoB gene sequencing identified AM-31 isolate as Aeromonas hydrophila and AM-05 as Aeromonas jandaei. Symptoms similar to that of natural infection were observed on re-infecting both bacteria to disease-free A. testudineus, which confirmed their virulence. LC was determined at 1.3 × 10 (A. hydrophila) and 2.5 × 10 (A. jandaei) CFU per fish in intraperitoneal injection. Further, PCR amplification of specific genes responsible for virulence (aerolysin and enterotoxin) confirmed pathogenicity of both bacteria. Histopathology of kidney and liver in the experimentally-infected fishes revealed haemorrhage, tubular degeneration and vacuolation. Antibiotic profiles were also assessed for both bacteria. To the best of our knowledge, the present work is a first report on the mortality of farmed climbing perch naturally-infected by A. hydrophila as well as A. jandaei, with no records of pathogenicity of the latter in this fish.
Topics: Aeromonas; Aeromonas hydrophila; Animals; Fish Diseases; Gram-Negative Bacterial Infections; Hemorrhagic Septicemia; Perches
PubMed: 33712685
DOI: 10.1038/s41598-021-84997-x -
Journal of Clinical Microbiology Mar 1991Exudate removed from an infection that developed below the left eye of a 10-year-old male following a previously inflicted wound after aquatic exposure was cultured and...
Exudate removed from an infection that developed below the left eye of a 10-year-old male following a previously inflicted wound after aquatic exposure was cultured and revealed two different Aeromonas spp. Further characterization showed that one strain was phenotypically identical to Aeromonas veronii, while the other strain was confirmed by DNA hybridization analysis to be Aeromonas jandaei sp. nov. This is the first report of these more recently described aeromonads, thus far rarely reported from clinical disease, occurring simultaneously in a human infection.
Topics: Aeromonas; Bacterial Infections; Child; DNA, Bacterial; Drug Resistance, Microbial; Fresh Water; Humans; Male; Nucleic Acid Hybridization; Species Specificity; Water Microbiology; Wound Infection
PubMed: 2037674
DOI: 10.1128/jcm.29.3.565-569.1991 -
Genome Announcements Jun 2018We report here the whole-genome sequencing results of two bacterial isolates, IMET J and IMET F, that inhibit (possibly due to denitrifying gene clusters) and promote...
Draft Genome Sequences of Cloacibacterium normanense IMET F, a Microalgal Growth-Promoting Bacterium, and Aeromonas jandaei IMET J, a Microalgal Growth-Inhibiting Bacterium.
We report here the whole-genome sequencing results of two bacterial isolates, IMET J and IMET F, that inhibit (possibly due to denitrifying gene clusters) and promote (possibly due to an ammonification system), respectively, the growth of the microalgal strains HTB1 and 1807.
PubMed: 29903817
DOI: 10.1128/genomeA.00503-18 -
FEMS Immunology and Medical Microbiology Apr 1997An experimental study of five isolates of Aeromonas jandaei and 12 of A. trota was carried out to examine if they produced an enterotoxic substance, and if so, to...
An experimental study of five isolates of Aeromonas jandaei and 12 of A. trota was carried out to examine if they produced an enterotoxic substance, and if so, to characterise that factor and to see if it caused any mucosal damage. Only two of the A. trota strains caused fluid accumulation in the initial rabbit ileal loop (RIL) tests. The remaining strains did so only after one to five sequential passages through RILs and once they caused a secretory response they showed a gradual enhancement of fluid outpouring after each subsequent passage. Inocula of approximately 1 x 10(5) viable cells and 0.25 ml of culture filtrate caused fluid accumulations comparable to those of toxigenic V. cholerae 569B. The enterotoxic factors of both organisms were inactivated when held at 56 degrees C for 20 min or 65 degrees C for 10 min and showed biological activity over a wide range of pH. The only histopathological change observed in the ileal loop was depletion of mucus from the goblet cells. These data thus indicate that strains of A. jandaei and A. trota may produce a heat-labile and pH-stable diarrhoeagenic substance that causes little or no damage to the intestinal mucosa, like that of other known heat-labile enterotoxins.
Topics: Aeromonas; Animals; Enterotoxins; Hydrogen-Ion Concentration; Ileum; Rabbits
PubMed: 9143882
DOI: 10.1111/j.1574-695X.1997.tb01018.x -
Journal of Clinical Microbiology Mar 1991A large numerical taxonomy study conducted in 1988 of 165 mostly clinical Aeromonas strains from diverse geographic sources produced a cluster (S = 84%, SSM) of four...
A large numerical taxonomy study conducted in 1988 of 165 mostly clinical Aeromonas strains from diverse geographic sources produced a cluster (S = 84%, SSM) of four sucrose-negative strains that included the DNA definition strain for DNA group 9 A. sobria (CDC 0787-80). These four strains, together with five additional strains received in 1989, were subjected to DNA-DNA hybridization (hydroxyapatite, 32P, 60 and 75 degrees C), and all eight strains were closely related to the ninth labeled DNA group 9 definition strain CDC 0787-80 (73 to 86% relatedness at 60 degrees C and 68 to 80% relatedness at 75 degrees C; percent divergence, 2.0 to 3.5). Type strains and DNA definition strains for all other established Aeromonas species were only 35 to 72% related (60 degrees C) to CDC 0787-80. We propose the name Aeromonas jandaei for this highly related group of nine strains, formerly known as DNA group 9 A. sobria. The type strain was designated ATCC 49568 (CDC 0787-80). The nine strains were examined at 36 degrees C and were found to be resistant to 0/129 (vibriostatic agent) and uniformly positive for oxidase, gas production from glucose, indole, lysine decarboxylase, arginine dihydrolase, o-nitrophenyl-beta-D-galactopyranoside, motility (25 degrees C), nitrate reduction, citrate utilization, hemolysis on sheep blood agar, and growth in Trypticase soy broth with no added NaCl. They all fermented D-glucose, D-mannitol, and mannose but did not ferment sucrose, cellobiose, L-arabinose, inositol, salicin, or D-sorbitol. They were uniformly negative for esculin and urea hydrolysis, elastase production, ornithine decarboxylation, and the string test. The antibiogram of A. jandaei resembled that of other aeromonads (resistance to ampicillin and cephalothin), but it differed from most other aeromonads because of resistance to single dilution of colistin and differed from clinical A. veronii biogroup sorbria (formerly A. sobria) by its nearly uniform resistance to cephalothin. The esculin-, sucrose-, and cellobiose-negative and colistin-resistant profile distinguished A. jandaei from other Aeromonas species. These A. jandaei strains were isolated from blood (two strains), wounds (two strains), diarrheal stools (four strains), and a prawn (one strain). The blood and wound isolates, in particular, suggest that there is a possible clinical significance for this species and justify identification of and further research on this group of motile aeromonads.
Topics: Aeromonas; Aged; Bacterial Infections; Child; DNA, Bacterial; Drug Resistance, Microbial; Humans; Male; Nucleic Acid Hybridization; Phenotype; Sepsis; Species Specificity; Sucrose
PubMed: 2037673
DOI: 10.1128/jcm.29.3.560-564.1991 -
Journal of Bacteriology Jun 1997We have isolated the gene encoding L-allo-threonine aldolase (L-allo-TA) from Aeromonas jandaei DK-39, a pyridoxal 5'-phosphate (PLP)-dependent enzyme that...
L-allo-threonine aldolase from Aeromonas jandaei DK-39: gene cloning, nucleotide sequencing, and identification of the pyridoxal 5'-phosphate-binding lysine residue by site-directed mutagenesis.
We have isolated the gene encoding L-allo-threonine aldolase (L-allo-TA) from Aeromonas jandaei DK-39, a pyridoxal 5'-phosphate (PLP)-dependent enzyme that stereospecifically catalyzes the interconversion of L-allo-threonine and glycine. The gene contains an open reading frame consisting of 1,014 nucleotides corresponding to 338 amino acid residues. The protein molecular weight was estimated to be 36,294, which is in good agreement with the subunit molecular weight of the enzyme determined by polyacrylamide gel electrophoresis. The enzyme was overexpressed in recombinant Escherichia coli cells and purified to homogeneity by one hydrophobic column chromatography step. The predicted amino acid sequence showed no significant similarity to those of the currently known PLP-dependent enzymes but displayed 40 and 41% identity with those of the hypothetical GLY1 protein of Saccharomyces cerevisiae and the GLY1-like protein of Caenorhabditis elegans, respectively. Accordingly, L-allo-TA might represent a new type of PLP-dependent enzyme. To determine the PLP-binding site of the enzyme, all of the three conserved lysine residues of L-allo-TA were replaced by alanine by site-directed mutagenesis. The purified mutant enzymes, K51A and K224A, showed properties similar to those of the wild type, while the mutant enzyme K199A was catalytically inactive, with corresponding disappearance of the absorption maximum at 420 nm. Thus, Lys199 of L-allo-TA probably functions as an essential catalytic residue forming an internal Schiff base with PLP of the enzyme to catalyze the reversible aldol reaction.
Topics: Aeromonas; Amino Acid Sequence; Base Sequence; Binding Sites; Cloning, Molecular; Genes, Bacterial; Glycine Hydroxymethyltransferase; Lysine; Molecular Sequence Data; Mutagenesis, Site-Directed; Pyridoxal Phosphate; Sequence Alignment
PubMed: 9171400
DOI: 10.1128/jb.179.11.3555-3560.1997 -
Journal of Food Protection May 2001Numbers and species of motile Aeromonas were determined in freshly caught freshwater fish, in the surrounding environment, and also during iced chilled storage of fish... (Comparative Study)
Comparative Study
Numbers and species of motile Aeromonas were determined in freshly caught freshwater fish, in the surrounding environment, and also during iced chilled storage of fish specimens. Although no significant differences were observed in water samples, initial levels for skin, gill, and intestines were significantly lower in farmed rainbow trout (Oncorhynchus mykiss) than in wild brown trout (Salmo trutta) and pike (Esox lucius). During storage of wild specimens, naturally occurring aeromonads grew fairly well on the surfaces of skin and body cavity. Of 171 strains assigned to the genus Aeromonas, 88% were identified to phenospecies and putative genospecies level by using comprehensive biochemical schemes. The isolates were allocated to putative hybridization groups (HGs) 1 and 3 Aeromonas hydrophila (29%); putative HG 8 Aeromonas veronii biovar sobria (19%); putative HG 2 Aeromonas bestiarum (18%); putative HG 9 Aeromonas jandaei (16%); putative HGs 4 and 5a Aeromonas caviae (2%); putative HG 12 Aeromonas schubertii (2%); and putative HG 11 (unnamed, 0.6%). The remaining 20 isolates (12%) resembled A. schubertii but could not be allocated to currently recognized phenospecies or to putative HGs. Although cultured rainbow trout yielded strains of putative HGs 1, 4, and 8, which appear to be of major clinical importance, most isolates assigned to putative HGs 1 and 8 were recovered from pike. Differences among HGs found in wild animals could be related to their origin (unpolluted rivers for brown trout and urban rivers for pike). The recovery of these aeromonads species was not related to sampling site. The initial levels of motile aeromonads, their behavior during storage, and the strong potential spoilage activity of most isolates confirm that these bacteria can contribute to deterioration of iced wild freshwater fish. Although adequate cooking would inactivate motile aeromonads, the high incidence of isolates belonging to gastroenteritis-associated HGs should be regarded as a potential health concern, particularly for susceptible populations when there is a possibility of cross-contamination.
Topics: Aeromonas; Animals; Animals, Wild; Aquaculture; Esocidae; Fishes; Trout; Water Microbiology
PubMed: 11348001
DOI: 10.4315/0362-028x-64.5.687 -
Applied and Environmental Microbiology Oct 2006Eighty-one tetracycline-resistant Aeromonas sp. strains were isolated from farm-raised catfish. Morphological and biochemical characteristics indicated that 23 of the 81...
Eighty-one tetracycline-resistant Aeromonas sp. strains were isolated from farm-raised catfish. Morphological and biochemical characteristics indicated that 23 of the 81 aeromonads were Aeromonas hydrophila, 7 isolates were Aeromonas trota, 6 isolates were Aeromonas caviae, 42 isolates were Aeromonas veronii, and 3 isolates were Aeromonas jandaei. However, the AluI and MboI restriction fragment length polymorphism (RFLP) patterns of the PCR-amplified 1.4-kb 16S rRNA gene from all 81 tetracycline-resistant aeromonads from catfish were identical to the RFLP banding patterns of A. veronii ATCC 35626, indicating that all 81 isolates were strains of A. veronii. A multiplex PCR assay successfully amplified the 5 tetracycline-resistant genes (tetA to E) from the genomic DNA of all 81 isolates. The assay determined that tetE was the dominant gene occurring in 73/81 (90.0%) of the aeromonads. Plasmids (2.0 to 20 kb) were isolated from 33 of the 81 isolates. Dendrogram analysis of the SpeI pulsed-field gel electrophoresis identified 15 distinct macrorestriction patterns among the isolates. Our results indicate the need for use of 16S rRNA in the identification of Aeromonas spp. and the prevalence of catfish as a reservoir of tet genes.
Topics: Aeromonas; Animals; Bacterial Typing Techniques; Catfishes; Drug Resistance, Bacterial; Electrophoresis, Gel, Pulsed-Field; Food Microbiology; Plasmids; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; RNA, Ribosomal, 16S; Tetracyclines
PubMed: 17021193
DOI: 10.1128/AEM.00271-06 -
Journal of Bacteriology Mar 1997Aeromonas jandaei AER 14 (formerly Aeromonas sobria AER 14) expresses three inducible beta-lactamases, AsbA1, OXA-12 (AsbB1), and AsbM1. Mutant strains that...
Aeromonas jandaei AER 14 (formerly Aeromonas sobria AER 14) expresses three inducible beta-lactamases, AsbA1, OXA-12 (AsbB1), and AsbM1. Mutant strains that constitutively overexpress all three enzyme simultaneously, suggesting that they share a common regulatory pathway, have been isolated. Detectable expression of the cloned genes of AsbA1 and OXA-12 in some Escherichia coli K-12 laboratory strains is achieved only in the presence of a blp mutation. These mutations map to the cre operon at 0 min, which encodes a classical two-component regulatory system of unknown function. Two regulatory elements from A. jandaei which permit high-level constitutive expression of OXA-12 in E. coli were cloned. Both loci encode proteins with characteristics of response regulator proteins of two-component regulatory systems. One of these loci, designated blrA, bestowed constitutive expression of all three beta-lactamases in A. jandaei AER 14 when present on a multicopy plasmid, confirming its role in the regulatory pathway of beta-lactamase production in this organism.
Topics: Aeromonas; Amino Acid Sequence; Bacterial Proteins; Base Sequence; Cloning, Molecular; Gene Expression Regulation, Bacterial; Molecular Sequence Data; Regulon; beta-Lactamases
PubMed: 9068648
DOI: 10.1128/jb.179.6.2006-2013.1997