Vibriosis Incidents in Marine Finfish Farms: Prevalence, Diagnosis of Pathogens using 16S rRNA, Histopathology, and In Vitro Antibacterial Evaluation Against Isolated Vibrio spp using Antibiotics and Probiotics

Abstract Background Rice forms a significant portion of food consumed in most household worldwide. Rice production has been hampered by soil factors such as ferruginousity which has limited phosphorus availability; an important mineral component for the growth and yield of rice. The presence of phosphate-solubilizing bacteria (PSB) in soils has been reported to enhance phosphate availability. In view of this, the present study employed three bacteria species (BCAC2, EMBF2 and BCAF1) that were previously isolated and proved P solubilization capacities as inocula to investigate the growth response of rice germinants in an in vitro setup. The bacteria isolates were first identified using 16S rRNA gene sequencing and then applied as inoculum. The inolula were prepared in three concentrations (10, 7.5 and 5.0 ml) following McFarland standard. Viable rice (var. FARO 44) seeds were sown in petri dishes and then inoculated with the three inocula at the different concentrations. The setup was studied for 28 days. Results 16S rRNA gene sequencing identified the isolates as: isolate BCAC2= Bacillus cereus strain GGBSU-1, isolate BCAF1= Proteus mirabilis strain TL14-1 and isolate EMBF2= Klebsiella variicola strain AUH-KAM-9. Significant improvement in rice germination, morphology, physiology and biomass parameters in the bacteria-inoculated setups was observed compared to the control. Germination percentage after 4 days was 100 % in the inoculated rice germinants compared to 65% in the control (NiS). Similarly, inoculation with the test isolates enhanced water-use efficiency by over 40%. The rice seedlings inoculated with Bacillus cereus strain GGBSU-1 (BiS) showed no signs of chlorosis and necrosis throughout the study period as against those inoculated with Proteus mirabilis strain TL14-1 (PiS) and Klebsiella variicola strain AUH-KAM-9 (KiS). Significant increase in chlorophyll-a, chlorophyll-b and alpha amylase was observed in the rice seedlings inoculated with BiS as against the NiS. Conclusion Inoculating rice seeds with Bacillus cereus strain GGBSU-1, Proteus mirabilis strain TL14-1 and Klebsiella variicola strain AUH-KAM-9 in an in vitro media significantly improved growth parameters of the test plant. Bacillus cereus strain GGBSU-1 showed higher efficiency due to a more improved growth properties observed.

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Live Bacillus subtilis natto Promotes Rumen Fermentation by Modulating Rumen Microbiota In Vitro

Animals ◽

10.3390/ani11061519 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1519

Author(s):

Meinan Chang ◽

Fengtao Ma ◽

Jingya Wei ◽

Junhao Liu ◽

Xuemei Nan ◽

...

Keyword(s):

Bacillus Subtilis ◽

16S Rrna ◽

Rumen Fluid ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Rumen Fermentation ◽

Rrna Gene ◽

Bacillus Subtilis Natto ◽

Rrna Gene Sequencing

Previous studies have shown that Bacillus subtilis natto affects rumen fermentation and rumen microbial community structure, which are limited to detect a few microbial abundances using traditional methods. However, the regulation of B. subtilis natto on rumen microorganisms and the mechanisms of microbiota that affect rumen fermentation is still unclear. This study explored the effects of live and autoclaved B. subtilis natto on ruminal microbial composition and diversity in vitro using 16S rRNA gene sequencing and the underlying mechanisms. Rumen fluid was collected, allocated to thirty-six bottles, and divided into three treatments: CTR, blank control group without B. subtilis natto; LBS, CTR with 109 cfu of live B. subtilis natto; and ABS, CTR with 109 cfu of autoclaved B. subtilis natto. The rumen fluid was collected after 0, 6, 12, and 24 h of fermentation, and pH, ammonia nitrogen (NH3-N), microbial protein (MCP), and volatile fatty acids (VFAs) were determined. The diversity and composition of rumen microbiota were assessed by 16S rRNA gene sequencing. The results revealed LBS affected the concentrations of NH3-N, MCP, and VFAs (p < 0.05), especially after 12 h, which might be attributed to changes in 18 genera. Whereas ABS only enhanced pH and NH3-N concentration compared with the CTR group (p < 0.05), which might be associated with changes in six genera. Supplementation with live B. subtilis natto improved ruminal NH3-N and propionate concentrations, indicating that live bacteria were better than autoclaved ones. This study advances our understanding of B. subtilis natto in promoting ruminal fermentation, providing a new perspective for the precise utilization of B. subtilis natto in dairy rations.

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IN VITRO ANTAGONISTIC ACTIVITIES OF INDONESIAN MARINE SPONGE AAPTOS AAPTOS AND CALLYSPONGIA PSEUDORETICULATA EXTRACTS AND THEIR TOXICITY AGAINST Vibrio spp.

Indonesian Aquaculture Journal ◽

10.15578/iaj.6.2.2011.173-182 ◽

2011 ◽

Vol 6 (2) ◽

pp. 173 ◽

Cited By ~ 1

Author(s):

Rosmiati Rosmiati ◽

Habsah Mohamad ◽

Tengku Sifzizul Tengku Muhammad ◽

Najiah Musa ◽

Aziz Ahmad ◽

...

Keyword(s):

Antibacterial Activity ◽

Aqueous Extract ◽

Pathogenic Bacteria ◽

Vibrio Harveyi ◽

Diffusion Method ◽

Larval Rearing ◽

Butanol Extract ◽

Vibrio Spp ◽

Mic Value

Vibriosis is one of diseases which often results in mass mortality of Penaeus monodon larval rearing systems. It attacks shrimp of all stages in zoea, mysis and shrimp postlarva stage. This disease is caused by Vibrio spp, particularly Vibrio harveyi (a luminescent bacterium). Several kinds of antibiotics and chemical material have been used to overcome the disease but they have side effects to environment and human. The searching of bioactive compounds as an alternative treatment has been done for multi purposes. In this study diethyl eter, butanol and aqueous extract of Indonesian sponges Aaptos aaptos and Callyspongia pseudoreticulata were tested for in vitro activity against Vibrio spp. and Vibrio harveyi by using disc diffusion method. The result showed that all extracts of Aaptos aaptos gave a positive antibacterial activity towards those pathogenic bacteria. Meanwhile, only butanol extract of Callyspongia pseudoreticulata obtained to exhibit an antibacterial activity on those pathogenic bacteria. The strong anti-vibrio activity were shown by butanol and aqueous extract of Aaptos aaptos with the minimum inhibitory concentration (MIC) value of 0.313 and 0.625 mg/mL, respectively. Whilst, the butanol extract of Callyspongia pseudoreticulata indicated a low antibacterial activity with the MIC value of 10 mg/mL. Toxicity of those active extracts was evaluated by Brine Shrimp Lethality Test (BST). Interestingly, butanol and aqueous extracts of Aaptos aaptos did not show any toxic effect in Artemia salina larvae up to 8 x MIC (2.504 mg/mL and 5.000 mg/mL). It is the first report for the anti-vibr io activity of both Aaptos aaptos and Callyspongia pseudoreticulata. This results suggest that Aaptos aaptos has a potential to be used as a source of alternative compound to vibriosis prevention for mariculture.

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Apis andreniformis associated Actinomycetes show antimicrobial activity against black rot pathogen (Xanthomonas campestris pv. campestris)

PeerJ ◽

10.7717/peerj.12097 ◽

2021 ◽

Vol 9 ◽

pp. e12097

Author(s):

Yaowanoot Promnuan ◽

Saran Promsai ◽

Wasu Pathom-aree ◽

Sujinan Meelai

Keyword(s):

Antimicrobial Activity ◽

16S Rrna ◽

16S Rrna Gene ◽

Honey Bee ◽

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Rrna Gene ◽

Apis Andreniformis

This study aimed to investigate cultivable actinomycetes associated with rare honey bee species in Thailand and their antagonistic activity against plant pathogenic bacteria. Actinomycetes were selectively isolated from the black dwarf honey bee (Apis andreniformis). A total of 64 actinomycete isolates were obtained with Streptomyces as the predominant genus (84.4%) followed by Micromonospora (7.8%), Nonomuraea (4.7%) and Actinomadura (3.1%). All isolates were screened for antimicrobial activity against Xanthomonas campestris pv. campestris, Pectobacterium carotovorum and Pseudomonas syringae pv. sesame. Three isolates inhibited the growth of X. campestris pv. campestris during in vitro screening. The crude extracts of two isolates (ASC3-2 and ASC5-7P) had a minimum inhibitory concentration (MIC) of 128 mg L−1against X. campestris pv. campestris. For isolate ACZ2-27, its crude extract showed stronger inhibitory effect with a lower MIC value of 64 mg L−1 against X. campestris pv. campestris. These three active isolates were identified as members of the genus Streptomyces based on their 16S rRNA gene sequences. Phylogenetic analysis based on the maximum likelihood algorithm showed that isolate ACZ2-27, ASC3-2 and ASC5-7P were closely related to Streptomyces misionensis NBRC 13063T (99.71%), Streptomyces cacaoi subsp. cacaoi NBRC 12748T (100%) and Streptomyces puniceus NBRC 12811T (100%), respectively. In addition, representative isolates from non-Streptomyces groups were identified by 16S rRNA gene sequence analysis. High similarities were found with members of the genera Actinomadura, Micromonospora and Nonomuraea. Our study provides evidence of actinomycetes associated with the black dwarf honey bee including members of rare genera. Antimicrobial potential of these insect associated Streptomyces was also demonstrated especially the antibacterial activity against phytopathogenic bacteria.

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Mutations Conferring Aminoglycoside and Spectinomycin Resistance in Borrelia burgdorferi

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.2.445-452.2006 ◽

2006 ◽

Vol 50 (2) ◽

pp. 445-452 ◽

Cited By ~ 39

Author(s):

Daniel Criswell ◽

Virginia L. Tobiason ◽

J. Stephen Lodmell ◽

D. Scott Samuels

Keyword(s):

16S Rrna ◽

Borrelia Burgdorferi ◽

Type Strain ◽

Wild Type Strain ◽

Small Subunit ◽

Wild Type ◽

Spectinomycin Resistance ◽

E Coli ◽

Resistant Mutants

ABSTRACT We have isolated and characterized in vitro mutants of the Lyme disease agent Borrelia burgdorferi that are resistant to spectinomycin, kanamycin, gentamicin, or streptomycin, antibiotics that target the small subunit of the ribosome. 16S rRNA mutations A1185G and C1186U, homologous to Escherichia coli nucleotides A1191 and C1192, conferred >2,200-fold and 1,300-fold resistance to spectinomycin, respectively. A 16S rRNA A1402G mutation, homologous to E. coli A1408, conferred >90-fold resistance to kanamycin and >240-fold resistance to gentamicin. Two mutations were identified in the gene for ribosomal protein S12, at a site homologous to E. coli residue Lys-87, in mutants selected in streptomycin. Substitutions at codon 88, K88R and K88E, conferred 7-fold resistance and 10-fold resistance, respectively, to streptomycin on B. burgdorferi. The 16S rRNA A1185G and C1186U mutations, associated with spectinomycin resistance, appeared in a population of B. burgdorferi parental strain B31 at a high frequency of 6 × 10−6. These spectinomycin-resistant mutants successfully competed with the wild-type strain during 100 generations of coculture in vitro. The aminoglycoside-resistant mutants appeared at a frequency of 3 × 10−9 to 1 ×10−7 in a population and were unable to compete with wild-type strain B31 after 100 generations. This is the first description of mutations in the B. burgdorferi ribosome that confer resistance to antibiotics. These results have implications for the evolution of antibiotic resistance, because the 16S rRNA mutations conferring spectinomycin resistance have no significant fitness cost in vitro, and for the development of new selectable markers.

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In vitro and in vivo biofilm forming Vibrio spp: A significant threat in aquaculture

Process Biochemistry ◽

10.1016/j.procbio.2020.04.029 ◽

2020 ◽

Vol 94 ◽

pp. 213-223 ◽

Cited By ~ 3

Author(s):

Manivel Arunkumar ◽

Felix LewisOscar ◽

Nooruddin Thajuddin ◽

Arivalagan Pugazhendhi ◽

Chari Nithya

Keyword(s):

Vibrio Spp

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Inorganic Phosphate Solubilization by a Novel Isolated Bacterial Strain Enterobacter sp. ITCB-09 and Its Application Potential as Biofertilizer

Agriculture ◽

10.3390/agriculture10090383 ◽

2020 ◽

Vol 10 (9) ◽

pp. 383 ◽

Cited By ~ 3

Author(s):

Gustavo Enrique Mendoza-Arroyo ◽

Manuel Jesús Chan-Bacab ◽

Ruth Noemi Aguila-Ramírez ◽

Benjamín Otto Ortega-Morales ◽

René Efraín Canché Solís ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Inorganic Phosphate ◽

Extracellular Polymeric Substances ◽

Phosphate Solubilization ◽

Rrna Gene ◽

Bacterial Strains ◽

Habanero Pepper ◽

Phosphate Solubilizing

The excessive use of fertilizers in agriculture is mainly due to the recognized plant requirements for soluble phosphorus. This problem has limited the implementation of sustainable agriculture. A viable alternative is to use phosphate solubilizing soil microorganisms. This work aimed to isolate inorganic phosphorus-solubilizing bacteria from the soils of agroecosystems, to select and identify, based on sequencing and phylogenetic analysis of the 16S rRNA gene, the bacterium with the highest capacity for in vitro solubilization of inorganic phosphate. Additionally, we aimed to determine its primary phosphate solubilizing mechanisms and to evaluate its effect on Habanero pepper seedlings growth. A total of 21 bacterial strains were isolated by their activity on Pikovskaya agar. Of these, strain ITCB-09 exhibited the highest ability to solubilize inorganic phosphate (865.98 µg/mL) through the production of organic acids. This strain produced extracellular polymeric substances and siderophores that have ecological implications for phosphate solubilization. 16S rRNA gene sequence analysis revealed that strain ITCB-09 belongs to the genus Enterobacter. Enterobacter sp. ITCB-09, especially when immobilized in beads, had a positive effect on Capsicum chinense Jacq. seedling growth, indicating its potential as a biofertilizer.

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