Bacterial Species
Recently Published Documents





2024 ◽  
Vol 84 ◽  
R. Ullah ◽  
A. W. Qureshi ◽  
A. Sajid ◽  
I. Khan ◽  
A. Ullah ◽  

Abstract Fish is the main source of animal protein for human diet. The aim of this study was to find out prevalence of pathogenic bacteria of two selected economically important fish of Pakistan namely Mahseer (Tor putitora) and Silver carp (Hypophthalmichthys molitrix). Live fish samples from hatcheries and dead fish samples from different markets of study area were randomly collected. The fish samples were analyzed for isolation, identification and prevalence of bacteria. The isolated bacteria from study fish were identified through biochemical test and about 10 species of pathogenic bacteria were identified including the pathogenic bacteria to human and fish namely, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus iniae, Serratia spp. Citrobacter spp. Stenotrophomonas spp. Bacillus spp. and Salmonella spp. The bacterial percentage frequency of occurrence in Silver carp and Mahseer fish showed Pseudomonas aeruginosa 21.42%, Staphylococcus epidermidis 17.85%, Escherichia coli 11.90%, Staphylococcus aureus 9.52%, Citrobacter spp. 9.52%, Serratia spp. 8.33%, Streptococcus iniae 7.14%, Stenotrophomonas spp. 5.95%, Bacillus spp. 4.76% and Salmonella spp. 3.57%. The study revealed that Fish samples of Mahseer and Silver carp that were collected from markets have found more isolates (10 bacterial species) than did the fresh fish pond samples (03 bacterial species) of hatcheries. The occurrence of pathogenic bacteria in study fish showed risk factor for public health consumers.

Ajayi AO ◽  

This study shows the bactericidal effect of Electromagnetic Field on fruit juice microbes. Short shelf-life period of fruit juice caused by spoilage organisms has limiting factor for its economy value. The Eighteen microorganisms isolated from both fresh and spoilt fruit samples (Pineapple and Apple), and identified during the study include, twelve (12) bacteria and Six (6) fungi, out of which only the bacterial isolates were exposed to electromagnetic field of 0mG, 500mG, and 5000mG for thirty minutes. The bacteria species were Leuconostoc mesentroides, Bacillus species, Lactobacillus brevis, Microbacterium species, Clostridium species, Bacillus cereus, Acetobacter aceti, and Staphylococcus aureus. The Gram negative bacteria isolates were Erwinia carotovora, Erwinia ananas, and Proteus species. Exposure of the isolates to an electromagnetic field of 0mG, 500mG and 5000mG showed a decrease in some electromagnetic field magnitude. This study shows reduction in growth range among most bacterial species tested at 500mG electromagnetic radiation exposure, but the growth of many of these bacterial species were triggered at 5000mG electromagnetic radiation exposure. This may mean an initiation of: adaptation mechanism, growth mechanism in some microorganism, and sugar content of the fruit juice from which they are being isolated. The exposure of the bacteria to electromagnetic field elicited detectable responses therefore depends on the adaptation mechanism of each bacteria and sugar content of the fruit from which it is being isolated from. Thus, future research can be done to optimize the limits specified for target microbes that are strength and frequency of this EMF in diseases control.

2022 ◽  
Amy Switzer ◽  
Lynn Burchell ◽  
Panagiotis Mitsidis ◽  
Ramesh Wigneshweraraj

The canonical function of a bacterial sigma factor is to determine the gene specificity of the RNA polymerase (RNAP). In several diverse bacterial species, the sigma 54 factor uniquely confers distinct functional and regulatory properties on the RNAP. A hallmark feature of the sigma 54-RNAP is the obligatory requirement for an activator ATPase to allow transcription initiation. The genes that rely upon sigma 54 for their transcription have a wide range of different functions suggesting that the repertoire of functions performed by genes, directly or indirectly affected by sigma 54, is not yet exhaustive. By comparing the non-planktonic growth properties of prototypical enteropathogenic, uropathogenic and non-pathogenic Escherichia coli strains devoid of sigma 54, we uncovered sigma 54 as a determinant of homogenous non-planktonic growth specifically in the uropathogenic strain. Notably, bacteria devoid of individual activator ATPases of the sigma 54-RNAP do not phenocopy the sigma 54 mutant strain. It seems that sigma 54's role as a determinant of homogenous non-planktonic growth represents a putative non-canonical function of sigma 54 in regulating genetic information flow.

Carolina Sanitá Tafner Ferreira ◽  
Camila Marconi ◽  
Cristina M. G. L. Parada ◽  
Jacques Ravel ◽  
Marcia Guimaraes da Silva

IntroductionSialidase activity in the cervicovaginal fluid (CVF) is associated with microscopic findings of bacterial vaginosis (BV). Sequencing of bacterial 16S rRNA gene in vaginal samples has revealed that the majority of microscopic BV cases fit into vaginal community-state type IV (CST IV), which was recently named “molecular-BV.” Bacterial vaginosis-associated bacterial species, such as Gardnerella spp., may act as sources of CVF sialidases. These hydrolases lead to impairment of local immunity and enable bacterial adhesion to epithelial and biofilm formation. However, the impact of CVL sialidase on microbiota components and diversity remains unknown.ObjectiveTo assess if CVF sialidase activity is associated with changes in bacterial components of CST IV.MethodsOne hundred forty women were cross-sectionally enrolled. The presence of molecular-BV (CST IV) was assessed by V3–V4 16S rRNA sequencing (Illumina). Fluorometric assays were performed using 2-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid (MUAN) for measuring sialidase activity in CVF samples. Linear discriminant analysis effect size (LEfSe) was performed to identify the differently enriched bacterial taxa in molecular-BV according to the status of CVF sialidase activity.ResultsForty-four participants (31.4%) had molecular-BV, of which 30 (68.2%) had sialidase activity at detectable levels. A total of 24 bacterial taxa were enriched in the presence of sialidase activity, while just two taxa were enriched in sialidase-negative samples.ConclusionSialidase activity in molecular-BV is associated with changes in bacterial components of the local microbiome. This association should be further investigated, since it may result in diminished local defenses against pathogens.

Insects ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 86
Xiaohui Yang ◽  
Yu Hui ◽  
Daohong Zhu ◽  
Yang Zeng ◽  
Lvquan Zhao ◽  

Dryocosmus kuriphilus (Hymenoptera: Cynipidae) induces galls on chestnut trees, which results in massive yield losses worldwide. Torymus sinensis (Hymenoptera: Torymidae) is a host-specific parasitoid that phenologically synchronizes with D. kuriphilus. Bacteria play important roles in the life cycle of galling insects. The aim of this research is to investigate the bacterial communities and predominant bacteria of D. kuriphilus, T. sinensis, D. kuriphilus galls and the galled twigs of Castanea mollissima. We sequenced the V5–V7 region of the bacterial 16S ribosomal RNA in D. kuriphilus, T. sinensis, D. kuriphilus galls and galled twigs using high-throughput sequencing for the first time. We provide the first evidence that D. kuriphilus shares most bacterial species with T. sinensis, D. kuriphilus galls and galled twigs. The predominant bacteria of D. kuriphilus are Serratia sp. and Pseudomonas sp. Furthermore, the bacterial community structures of D. kuriphilus and T. sinensis clearly differ from those of the other groups. Many species of the Serratia and Pseudomonas genera are plant pathogenic bacteria, and we suggest that D. kuriphilus may be a potential vector of plant pathogens. Furthermore, a total of 111 bacteria are common to D. kuriphilus adults, T. sinensis, D. kuriphilus galls and galled twigs, and we suggest that the bacteria may transmit horizontally among D. kuriphilus, T. sinensis, D. kuriphilus galls and galled twigs on the basis of their ecological associations.

2022 ◽  
Mark Achtman ◽  
Zhemin Zhou ◽  
Jane Charlesworth ◽  
Laura A. Baxter

The definition of bacterial species is traditionally a taxonomic issue while defining bacterial populations is done with population genetics. These assignments are species specific, and depend on the practitioner. Legacy multilocus sequence typing is commonly used to identify sequence types (STs) and clusters (ST Complexes). However, these approaches are not adequate for the millions of genomic sequences from bacterial pathogens that have been generated since 2012. EnteroBase ( automatically clusters core genome MLST alleles into hierarchical clusters (HierCC) after assembling annotated draft genomes from short read sequences. HierCC clusters span core sequence diversity from the species level down to individual transmission chains. Here we evaluate the ability of HierCC to correctly assign 100,000s of genomes to the species/subspecies and population levels for Salmonella, Clostridoides, Yersinia, Vibrio and Streptococcus. HierCC assignments were more consistent with maximum-likelihood super-trees of core SNPs or presence/absence of accessory genes than classical taxonomic assignments or 95% ANI. However, neither HierCC nor ANI were uniformly consistent with classical taxonomy of Streptococcus. HierCC was also consistent with legacy eBGs/ST Complexes in Salmonella or Escherichia and revealed differences in vertical inheritance of O serogroups. Thus, EnteroBase HierCC supports the automated identification of and assignment to species/subspecies and populations for multiple genera.

Chen Zheng-li ◽  
Peng Yu ◽  
Wu Guo-sheng ◽  
Hong Xu-Dong ◽  
Fan Hao ◽  

Abstract Burns destroy the skin barrier and alter the resident bacterial community, thereby facilitating bacterial infection. To treat a wound infection, it is necessary to understand the changes in the wound bacterial community structure. However, traditional bacterial cultures allow the identification of only readily growing or purposely cultured bacterial species and lack the capacity to detect changes in the bacterial community. In this study, 16S rRNA gene sequencing was used to detect alterations in the bacterial community structure in deep partial-thickness burn wounds on the back of Sprague-Dawley rats. These results were then compared with those obtained from the bacterial culture. Bacterial samples were collected prior to wounding and 1, 7, 14, and 21 days after wounding. The 16S rRNA gene sequence analysis showed that the number of resident bacterial species decreased after the burn. Both resident bacterial richness and diversity, which were significantly reduced after the burn, recovered following wound healing. The dominant resident strains also changed, but the inhibition of bacterial community structure was in a non-volatile equilibrium state, even in the early stage after healing. Furthermore, the correlation between wound and environmental bacteria increased with the occurrence of burns. Hence, the 16S rRNA gene sequence analysis reflected the bacterial condition of the wounds better than the bacterial culture. 16S rRNA sequencing in the Sprague-Dawley rat burn model can provide more information for the prevention and treatment of burn infections in clinical settings and promote further development in this field.

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262414
Ashley Winfred Nakawuki ◽  
Rebecca Nekaka ◽  
Lydia V. N. Ssenyonga ◽  
George Masifa ◽  
Dorreck Nuwasiima ◽  

Background Postpartum urinary Catheter-Related Infections (CRIs) are a significant cause of maternal sepsis. Several studies done have reported the presence of mixed populations of bacteria with a significant increase in Extended-Spectrum Beta-Lactamase (ESBL) Enterobacteriaceae spps, Methicillin-Resistant Staphylococcus aureus (MRSA), Multi-Drug Resistant (MDR) bacteria in urine and blood cultures of catheterized patients despite the use of prophylactic antibiotics. This study aimed at determining the bacterial species diversity and susceptibility patterns of indwelling urinary catheters from postpartum mothers attending Mbale Regional Referral Hospital (MRRH). Methods A cross-sectional study employing quantitative and qualitative was carried out in MRRH among postpartum mothers with urinary catheters and their care-takers. The purposive non-random sampling strategy was used to collect data using an interviewer-administered questionnaire for the quantitative data collection and in-depth interviews for qualitative data collection. All the data collection tools used were developed, pretested and validated. At the point of de-catheterization, Catheter tips from enrolled participants were cut about 2-3cm below the balloon aseptically into test-tube containing peptone water, sonication technique employed, and incubation done 24hours then cultured to ensure phenotypic identification. An antibiotic sensitivity test was performed using the disc diffusion method following Clinical and Laboratory Standards Institute (CLSI) guidelines. Quantitative data collected was entered in Microsoft Excel and then exported to STATA14 for statistical analysis. Thematic analysis was used to analyse and organise qualitative data by an inductive coding method using Nvivo 12 software. Results In this study, 208 postpartum mothers participated, the majority of whom were caesarean section mothers of age range 20–24 years and 17 care-takers with a median age of 32 years. The prevalence of catheter tips bacterial colonisation was 98% despite 88.5% of the participants being on broad-spectrum antibiotics. The average duration of catheterisation was 2 days. All bacteria isolates were potential uro-pathogens with a mean occurrence of 2 bacteria species in each urinary catheter tip. The rates of MDR to commonly used antibiotics were high. The urinary catheter size of greater than F14 and duration of catheterization greater than 2 days were significantly associated with the number of bacterial species isolated from each sample. The maintenance care and knowledge of care-urinary catheter care among the care-takers was found sub-optimal. Conclusion There was a high prevalence of catheter colonisation with bacterial spps diversity averaging 2 spps per sample despite use of broad spectrum antibiotics. The MDR rates were high, which calls for routine culture and sensitivity. Health workers practicing obstetric medicine need to pay attention to catheter sizes during catheterisation and its duration. Health education should be part of antenatal and postnatal care education.

2022 ◽  
Vol 23 (2) ◽  
pp. 725
Yasuyuki Nagasawa ◽  
Taro Misaki ◽  
Seigo Ito ◽  
Shuhei Naka ◽  
Kaoruko Wato ◽  

A relationship between IgA nephropathy (IgAN) and bacterial infection has been suspected. As IgAN is a chronic disease, bacteria that could cause chronic infection in oral areas might be pathogenetic bacteria candidates. Oral bacterial species related to dental caries and periodontitis should be candidates because these bacteria are well known to be pathogenic in chronic dental disease. Recently, several reports have indicated that collagen-binding protein (cnm)-(+) Streptococcs mutans is relate to the incidence of IgAN and the progression of IgAN. Among periodontal bacteria, Treponema denticola, Porphyromonas gingivalis and Campylobacte rectus were found to be related to the incidence of IgAN. These bacteria can cause IgAN-like histological findings in animal models. While the connection between oral bacterial infection, such as infection with S. mutans and periodontal bacteria, and the incidence of IgAN remains unclear, these bacterial infections might cause aberrantly glycosylated IgA1 in nasopharynx-associated lymphoid tissue, which has been reported to cause IgA deposition in mesangial areas in glomeruli, probably through the alteration of microRNAs related to the expression of glycosylation enzymes. The roles of other factors related to the incidence and progression of IgA, such as genes and cigarette smoking, can also be explained from the perspective of the relationship between these factors and oral bacteria. This review summarizes the relationship between IgAN and oral bacteria, such as cnm-(+) S. mutans and periodontal bacteria.

Sign in / Sign up

Export Citation Format

Share Document