Isolation and characterization of bacteria associated with silkworm gut under antibiotic-treated larval feeding

Abstract The impact of antibiotics on growth, cocoon production was assessed in addition to isolation and characterization of bacteria associated with silkworm gut of infected larvae. Larval rearing was maintained at recommended conditions of temperature and humidity. Silkworm larvae showing abnormal symptoms were collected from the control group and dissected for gut collection. Bacteria were isolated from the gut content by spreading on agar plates and incubated at 37 °C for 48 hrs. Bacterial identification and phylogenetic analysis were carried out by 16S rRNA gene sequencing. The isolated bacteria were subjected to antimicrobial susceptibility test (disc diffusion methods) by using Penicillin (10 µg/mL), Tetracycline (30 µg/mL), Amoxicillin (25 µg/mL), Ampicillin (10 µg/mL), and Erythromycin (15 µg/mL). All isolated strains showed positive results for the catalase test. We isolated and identified bacterial strains (n = 06) from the gut of healthy and diseased silkworm larvae. Based on the 16S rRNA gene sequence, isolated bacteria showed close relation with Serratia, Bacillus, and Pseudomonas spp. Notably, 83.3% of strains were resistant to Penicillin, Tetracycline, Amoxicillin, Ampicillin, and Erythromycin but 16.6% showed antibiotic susceptibility to the above-mentioned commonly used antibiotics. Silkworm larvae fed on penicillin-treated leaves showed significant improvement in larval weight, larval length, and cocoon production. Significantly higher larval weight (6.88g), larval length (5.84cm), and cocoon weight (1.33g) were recorded for larvae fed on leaves treated with penicillin as compared to other antibiotics. Isolated bacterial strains showed close relation with Serratia spp., Bacillus spp. and Pseudomonas spp.

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Isolation and Characterization of Endophytic Bacteria from Tembelekan (Lantana camara L.) as Antibacterial Compounds Producer

Current Biochemistry ◽

10.29244/cb.2.2.86-98 ◽

2015 ◽

Vol 2 (2) ◽

pp. 86-98

Author(s):

Dina Dyah Saputri ◽

Maria Bintang ◽

Fachriyan H Pasaribu

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Endophytic Bacteria ◽

Pathogenic Bacteria ◽

Lantana Camara ◽

Rrna Gene ◽

Antibacterial Compounds ◽

Isolation And Characterization ◽

Ms Analysis

Endophytic bacteria are microorganisms that live in the internal tissues of plants and have symbiotic mutualism with their host plants. Endophytic bacteria may produce secondary metabolites that can be developed for medical, agricultural, and industrial purposes. Lantana camara is a medicinal plant that has therapeutic potential to treat a variety of diseases such as fever, tuberculosis, rheumatism, asthma, and skin disease. The purpose of this study was to isolate and characterize endophytic bacteria from Lantana camara which has potential to produce antibacterial compounds. The method of this research include isolation of endophytic bacteria of Lantana camara. Antibacterial activity assay was done against four types of pathogenic bacteria i.e. Bacillus cereus, Escherichia coli, Staphylococcus aureus, and Salmonella enteritidis. Characterization of endophytic bacteria was by 16S rRNA gene analysis and identification of antibacterial compounds by GC-MS analysis. Isolation of endophytic bacteria from Lantana camara resulted in BT22 as a potential isolate. Analysis of 16S rRNA gene showed that the BT22 isolate was similar to Bacillus amyloliquefaciens YB-1402 with 99% identity. The results of GC-MS analysis showed some antibacterial compounds such as: Cyclohexanone, 2-[2-(1,3-dithiolan-2-yl)propyl]-6-methyl-3-(1-methylethyl), Octadecane (CAS) n-Octadecane and Tetracosane (CAS) n-Tetracosane.

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Molecular characterization of Nocardiopsis species from Didwana dry salt lake of Rajasthan, India

Journal of Applied and Natural Science ◽

10.31018/jans.v13i1.2574 ◽

2021 ◽

Vol 13 (1) ◽

pp. 396-401

Author(s):

Khushbu Parihar ◽

Alkesh Tak ◽

Praveen Gehlot ◽

Rakesh Pathak ◽

Sunil Kumar Singh

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Bioactive Compounds ◽

Salt Lake ◽

Bioactive Compound ◽

Rrna Gene ◽

Biochemical Tests ◽

Multiple Sequence ◽

Isolation And Characterization

The genus Nocardiopsis is well known to produce secondary metabolites especially antibacterial bioactive compound. Isolation and characterization of bioactive compounds producing novel isolates from unusual habitats are crucial. The present study was aimed to explore Didwana dry salt lake of Rajasthan state in India for the isolation and characterization of actinomycetes. The isolated actinomycetes isolates were characterized based on culture characteristics, biochemical tests and 16S rRNA gene sequencing. The 16S rRNA gene sequence analysis revealed that all the five isolates inhabiting soil of the said dry salt lake of Didwana, Rajasthan belonged to four species of Nocardiopsis viz., N. synnemataformans, N. potens, N. prasina and N. dassonvillei subsp. albirubida. The molecular identification based on 16S rRNA gene sequences was found accurate and robust. The phylogram generated through multiple sequence alignment of all the test isolates of Nocardiopsis revealed that the isolates aroused from a single branch and validated monophyletic association. The present study is the first report of exploring Nocardiopsis isolates from the dry salt lake. These characterized Nocardiopsis isolates isolated from Didwana dry salt lake habitat are novel stains and can be of significance in the detection and utilization of novel bioactive compounds.

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Isolation and characterization of a novel chlorpyrifos degrading flavobacterium species EMBS0145 by 16S rRNA gene sequencing

Interdisciplinary Sciences Computational Life Sciences ◽

10.1007/s12539-012-0207-9 ◽

2014 ◽

Vol 7 (1) ◽

pp. 1-6 ◽

Cited By ~ 5

Author(s):

P. Amareshwari ◽

Mayuri Bhatia ◽

K. Venkatesh ◽

A. Roja Rani ◽

G. V. Ravi ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Isolation And Characterization ◽

Rrna Gene Sequencing

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Isolation and Characterization of Two European Strains of Ehrlichia phagocytophila of Equine Origin

Clinical and Vaccine Immunology ◽

10.1128/cdli.9.2.341-343.2002 ◽

2002 ◽

Vol 9 (2) ◽

pp. 341-343 ◽

Cited By ~ 2

Author(s):

Anneli Bjöersdorff ◽

Bodil Bagert ◽

Robert F. Massung ◽

Asiya Gusa ◽

Ingvar Eliasson

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Dna Sequences ◽

Rrna Gene ◽

Granulocytic Ehrlichiosis ◽

Ehrlichia Phagocytophila ◽

Isolation And Characterization ◽

Operon Gene ◽

The 16S Rrna Gene

ABSTRACT We report the isolation and partial genetic characterization of two equine strains of granulocytic Ehrlichia of the genogroup Ehrlichia phagocytophila. Frozen whole-blood samples from two Swedish horses with laboratory-verified granulocytic ehrlichiosis were inoculated into HL-60 cell cultures. Granulocytic Ehrlichia was isolated and propagated from both horses. DNA extracts from the respective strains were amplified by PCR using primers directed towards the 16S rRNA gene, the groESL heat shock operon gene, and the ank gene. The amplified gene fragments were sequenced and compared to known sequences in the GenBank database. With respect to the 16S rRNA gene, the groESL gene, and the ank gene, the DNA sequences of the two equine Ehrlichia isolates were identical to sequences found in isolates from clinical cases of granulocytic ehrlichiosis in humans and domestic animals in Sweden. However, compared to amplified DNA from an American Ehrlichia strain of the E. phagocytophila genogroup, differences were found in the groESL gene and ank gene sequences.

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Identification and molecular characterization of Chryseobacterium vrystaatense ST1 isolated from oligomineral water of southeast Serbia

Archives of Biological Sciences ◽

10.2298/abs1203877t ◽

2012 ◽

Vol 64 (3) ◽

pp. 877-883

Author(s):

S. Tasic ◽

M. Kojic ◽

S. Stankovic ◽

D. Obradovic

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Molecular Characterization ◽

Universal Primers ◽

Rrna Gene ◽

Bacterial Strains ◽

Biochemical Tests ◽

First Time

The isolation and molecular characterization of bacterial strains isolated from water sources in the Vlasina Mountain in southeast Serbia, confirmed the presence of a new species Chryseobacterium vrystaatense ST1. This Gram- negative species showed an extremely low level of biochemical reactivity in biochemical tests. The gene for 16S rRNA was amplified by PCR using universal primers and sequenced. Comparison of 16S rRNA gene sequence and phenotypic features indicated that the isolate ST belonged to Chryseobacterium vrystaatense. A BLAST search of sequenced 1088 nucleotides of the 16S rRNA gene with all sequences deposited in the NCBI collection showed the highest similarity (98%) with the strain Chryseobacterium vrystaatense sp. nov., designated as strain R-23533. The very high homology of these two strains allowed classification of our strain at the species level, but some differences indicate, and indirectly confirm, that the isolate ST is an authentic representative. On the basis of these results, we could conclude that Chryseobacterium vrystaatense ST was for first time isolated in Serbia, which is particularly important when one bears in mind that there are only three sequences of this species deposited in the NCBI collection.

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Integral Characterization of the 16S rRNA Gene of Non-sporulating Bacteria and Its Action Against Anticarsia gemmatalis Hübner (Lepidoptera: Erebidae)

Journal of Agricultural Science ◽

10.5539/jas.v12n12p61 ◽

2020 ◽

Vol 12 (12) ◽

pp. 61

Author(s):

Higor de Oliveira Alves ◽

Mariana Davanzo Miranda ◽

Ricardo Antônio Polanczyk ◽

Joacir do Nascimento ◽

Janete Apparecida Desiderio ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Marker Gene ◽

Anticarsia Gemmatalis ◽

Phylogenetic Position ◽

Rrna Gene ◽

Bacterial Strains ◽

Velvetbean Caterpillar ◽

The 16S Rrna Gene

Brazil is the world’s largest producer of soybean (Glycine max), an extremely important legume due to its source of proteins and essential oils for humans and animals, besides to its applications in the various branches of industry. The velvetbean caterpillar [Anticarsia gemmatalis Hübner (Lepidoptera: Erebidae)] is a great pest that affects this crop and has been controlled by chemical and biological pesticides based on Bacillus thuringiensis. The objectives of this work were to prospect soil microorganisms, to characterize them using the 16S rRNA gene and to perform bioassays to analyze the lethality or subletality of these isolates against A. gemmatalis larvae. The DNA sequencing of the marker gene was complete, covering all conserved regions of it to determine the phylogenetic position of the isolates. Regarding to bioassays, subletality efficacy were low both for sporulant and for the non-sporulant bacterial strains tested. However, based on the signature by complete 16S rRNA analyses of the non-sporulating bacterial isolates, new characteristics worth of studying and prospecting biotechnologically became available.

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Microbiome of Odontogenic Abscesses

Microorganisms ◽

10.3390/microorganisms9061307 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1307

Author(s):

Sebastian Böttger ◽

Silke Zechel-Gran ◽

Daniel Schmermund ◽

Philipp Streckbein ◽

Jan-Falco Wilbrand ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Oral Microbiome ◽

Minor Role ◽

Rrna Gene ◽

Sequencing Analysis ◽

Bacterial Strains ◽

16S Rrna Gene Analysis ◽

Odontogenic Infections ◽

Odontogenic Abscess

Severe odontogenic abscesses are regularly caused by bacteria of the physiological oral microbiome. However, the culture of these bacteria is often prone to errors and sometimes does not result in any bacterial growth. Furthermore, various authors found completely different bacterial spectra in odontogenic abscesses. Experimental 16S rRNA gene next-generation sequencing analysis was used to identify the microbiome of the saliva and the pus in patients with a severe odontogenic infection. The microbiome of the saliva and the pus was determined for 50 patients with a severe odontogenic abscess. Perimandibular and submandibular abscesses were the most commonly observed diseases at 15 (30%) patients each. Polymicrobial infections were observed in 48 (96%) cases, while the picture of a mono-infection only occurred twice (4%). On average, 31.44 (±12.09) bacterial genera were detected in the pus and 41.32 (±9.00) in the saliva. In most cases, a predominantly anaerobic bacterial spectrum was found in the pus, while saliva showed a similar oral microbiome to healthy individuals. In the majority of cases, odontogenic infections are polymicrobial. Our results indicate that these are mainly caused by anaerobic bacterial strains and that aerobic and facultative anaerobe bacteria seem to play a more minor role than previously described by other authors. The 16S rRNA gene analysis detects significantly more bacteria than conventional methods and molecular methods should therefore become a part of routine diagnostics in medical microbiology.

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