scholarly journals 16S rRNA as an applied tool in the molecular characterization of genera and species of bacteria

Respuestas ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 127-137
Author(s):  
Liliana Yanet Suárez-Contreras ◽  
Luz Francy Yañez-Meneses
Keyword(s):  
16S Rrna ◽  
Molecular Identification ◽  
Phylogenetic Trees ◽  
Alcaligenes Faecalis ◽  
Achromobacter Xylosoxidans ◽  
Bacterial Strains ◽  
Phenotypic Characteristics ◽  
Bioinformatic Tools ◽  
The University

Bacterial identification is carried out by conventional methods based on phenotypic characteristics, since their implementation and costs are more easily accessible. However, molecular identification allows us to know the true identity of the genus and species. The molecular identification of 24 bacterial strains preserved in the Strain Bank of the University Francisco de Paula Santander, Campos Eliseos Experimental Center, identified under macroscopic and microscopic phenotypic criteria, was carried out. Initially, the strains preserved in saline solution were reactivated and characterized macro- and microscopically, then DNA extraction was performed and PCR was done to amplify the 16S rRNA region allowing access to the DNA sequence of interest; the samples were sent to be sequenced and through bioinformatic tools the identity of each bacterium was known. The strains: BLB003, BLB009, BLB011, BLB012, BLB014, BLB016, BLB018, BLB022, BLB023, BLB024, BLB033, were identified as Bacillus cereus; BLB010 as Bacillus thurigiensis; while BLB030, BLB031, BLB032, as Bacillus pumilus; BLB020 as Bacillus amyloliquefaciens; BLB001, BLB004, BLB007, and BLB037, formed the group of Bacillus subtilis; and it is possible that there are divergent ramifications between species of Bacillus in phylogenetic trees. Another grouping that was observed in the phylogenetic tree are the strains BLB019 and BLB029 that correspond to Achromobacter xylosoxidans and Alcaligenes faecalis respectively. Also another group BLB013 and BLB017, were identified as Stenotrophomonas maltophilia. It is important to take into account that sometimes 16S rRNA presents a low discrimination capacity for some genera and species due to recent divergences, it is necessary to complement the identification with the study of other genes.

scholarly journals Isolation and Characterization of L-Glutaminase producing Bacteria

2020 ◽  
Author(s):  
Rabia Saleem ◽  
Safia Ahmed
Keyword(s):  
Bacillus Subtilis ◽  
Carbon Source ◽  
Incubation Time ◽  
Stenotrophomonas Maltophilia ◽  
Alcaligenes Faecalis ◽  
Achromobacter Xylosoxidans ◽  
Bacterial Strains ◽  
16S Rrna Sequence ◽  
Isolation And Characterization

AbstractBeing a significant protein L-glutaminases discovers potential applications in various divisions running from nourishment industry to restorative and cure. It is generally disseminated in microbes, actinomycetes, yeast and organisms. Glutaminase is the principal enzyme that changes glutamine to glutamate. The samples were gathered from soil of Taxila, Wah Cantt and Quetta, Pakistan for the isolation of glutaminase producing bacteria. After primary screening, subordinate screening was done which includes multiple testification such as purification, observation of morphological characters and biochemical testing of bacterial strains along with 16S rRNA sequence homology testing. Five bacterial strains were selected showing glutaminase positive test in screening, enzyme production via fermentation and enzymatic and protein assays. Taxonomical characterization of the isolates identified them as Bacillus subtilis U1, Achromobacter xylosoxidans G1, Bacillus subtilis Q2, Stenotrophomonas maltophilia U3 and Alcaligenes faecalis S3. The optimization of different effectors such as incubation time, inducers, carbon source, pH, and nitrogen source were also put under consideration. There was slight difference among incubation of bacterial culture, overall, 36 hours of incubation time was the best for glutaminase production by all the strains. Optimal pH was around 9 in Achromobacter xylosoxidans G1 and Alcaligenes faecalis S3, pH 6 in Bacillus subtilis U1, pH 8 in Stenotrophomonas maltophilia U3, pH 6-8 in Bacillus subtilis Q2. Best glutaminase production was obtained at 37°C by Bacillus subtilis U1and Bacillus subtilis Q2, 30°C for Achromobacter xylosoxidans G1, Stenotrophomonas maltophilia U3 and 25°C by Alcaligenes faecalis S3. The carbon sources put fluctuated effects on activity of enzyme in such a way that glucose was the best carbon source for Bacillus subtilis U1and Bacillus subtilis Q2, Sorbitol for Achromobacter xylosoxidans G1 and Alcaligenes faecalis S3 while xylose was the best for Stenotrophomonas maltophilia U3. Yeast extract and Trypton were among good nitrogen sources for Achromobacter xylosoxidans G1 and of Bacillus subtilis U1 respectively. Glutamine was the best inducer for Bacillus subtilis Q2, Alcaligenes faecalis S3 and Stenotrophomonas maltophilia U3, while lysine for Achromobacter xylosoxidans G1 and glycine act as good inducer in case of Bacillus subtilis U1. After implementation of optimal conditions microbial L-glutaminase production can be achieved and the bacterial isolates have a great potential for production of glutaminase enzyme and their applications.

ISOLATION AND CHARACTERIZATION OF BIOTECHNOLOGY RELEVANT BACTERIA FROM MARINE ENVIRONMENT

2015 ◽  
Vol 77 (31) ◽  
Author(s):  
Suganthi Thevarajoo ◽  
Chitra Selvaratnam ◽  
Kian Mau Goh ◽  
Fazilah Abd. Manan ◽  
Zaharah Ibrahim ◽  
...  
Keyword(s):  
16S Rrna ◽  
Marine Environment ◽  
Antibiotic Sensitivity ◽  
Marine Microorganisms ◽  
Bacterial Strains ◽  
Biochemical Tests ◽  
16S Rrna Sequence ◽  
Gram Staining ◽  
Isolation And Characterization

Marine environment remained as largely unexplored source for researchers to discover marine microorganisms with novel properties. This study aims to isolate marine bacteria from the seashore of Desaru, Malaysia. Totally, six bacterial strains were successfully obtained and were identified by complete 16S rRNA sequencing. The characterizations of bacterial strains were performed based on morphological tests, Gram-staining, biochemical tests, and antibiotic sensitivity. The 16S rRNA sequence of D-2, D-4, D-7, D-15, D-31, and D-33 revealed a high identity of 97 to 99% with taxa belong to genera of Pseudomonas, Marinomonas, Exiquobacterium, Micrococcus, Pseudoalteromonas, and Shewanella respectively. Strain D-31 exhibited higher tolerance towards antibiotics kanamycin, ampicillin, and erythromycin while the growth of other strains were retarded by at least two of these antibiotics. We further characterized strain D-4 and D-31 that belonged to Marinomonas sp. and Pseudoalteromonas sp.. Both genera are interesting as earlier researchers have discovered new antibacterial substances, industrial enzymes and unique secondary metabolites.

Isolation and Molecular Characterization of Riemerella anatipestifer from Domesticated Ducks of Assam, India

2021 ◽  
Author(s):  
M.K. Doley ◽  
S. Das ◽  
R.K. Sharma ◽  
P. Borah ◽  
D.K. Sarma ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Molecular Characterization ◽  
Molecular Identification ◽  
Rrna Gene ◽  
Eastern Region ◽  
Riemerella Anatipestifer ◽  
Field Samples ◽  
Apparently Healthy

Background: Riemerella anatipestifer (R. anatipestifer) is a gram negative, microaerophilic, non-motile, bipolar bacteria. High genetic diversity and molecular differentiation were reported among field isolates. Although the bacterium causes one of the most economically important duck diseases in the north-eastern region of India, little work has been done on isolation, identification and molecular characterization of the bacteria. Hence, the present investigation was undertaken with a view to characterize the R. anatipestifer isolates from ducks of Assam.Methods: Phenotypic and molecular identification of R. anatipestifer isolates from domesticated ducks of Assam, India were carried out during the period from February, 2019 to January 2020. A total of 624 samples (Ocular swab, throat swab, liver, spleen, kidney, brain, heart, lung) from ducks comprising of apparently healthy, ailing and dead ducks were collected from five districts of Assam, India were processed to isolate and identify the bacteria. The tentative identification of the bacteria was done based on phenotypic characteristics viz., colony morphology, growth characteristics and biochemical reactions. All the phenotypically positive isolates were further subjected to molecular identification based on PCR assay targeting 16S rRNA gene and ERIC sequence.Result: The bacteria could be isolated from different field samples. The highest percentage of the samples that yielded the bacteria are from brain (76%) followed by spleen (74%) of dead ducks and less number of ocular swab (33%) from apparently healthy ducks were found positive. Sequencing of the amplified product of the selected R. anatipestifer isolates targeting 16S rRNA gene revealed homology percentage of 96.5-100%. Further, sequences representing five geographical locations were submitted to NCBI gene bank. Phylogenetic studies of the isolates indicated that there is prevalence of at least two genetically different strains of R. anatipestifer in the study area. The study suggested that the R. anatipestifer infection is endemic in Assam causing varying rate of morbidity (39%) and mortality (53%) and molecular based confirmation is necessary besides phenotypic identification.

scholarly journals Massilia dura sp. nov., Massilia albidiflava sp. nov., Massilia plicata sp. nov. and Massilia lutea sp. nov., isolated from soils in China

2006 ◽  
Vol 56 (2) ◽  
pp. 459-463 ◽  
Author(s):  
Yu-Qin Zhang ◽  
Wen-Jun Li ◽  
Ke-Yun Zhang ◽  
Xin-Peng Tian ◽  
Yi Jiang ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Dna Hybridization ◽  
Type Strain ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
16S Rrna Gene Sequences ◽  
Phenotypic Characteristics ◽  
Gene Sequence Analysis

Four Gram-negative, motile, rod-shaped bacterial strains were isolated from soil samples collected from south-east China. A taxonomic study including phylogenetic analysis based on 16S rRNA gene sequences and phenotypic characteristics was performed. DNA G+C contents of the four strains were 63–66 mol%. Their predominant ubiquinone was Q-8. The fatty acid profiles contained C16 : 1 ω7c (36·9–54·7 %) and C16 : 0 (22·8–25·5 %) as the major components. Based on their phenotypic characteristics, phylogenetic position as determined by 16S rRNA gene sequence analysis and DNA–DNA hybridization results, the four isolates are considered to represent four novel species of the genus Massilia, for which the names Massilia dura sp. nov. (type strain 16T=CCTCC AB 204070T=KCTC 12342T), Massilia albidiflava sp. nov. (type strain 45T=CCTCC AB 204071T=KCTC 12343T), Massilia plicata sp. nov. (type strain 76T=CCTCC AB 204072T=KCTC 12344T) and Massilia lutea sp. nov. (type strain 101T=CCTCC AB 204073T=KCTC 12345T) are proposed.

scholarly journals Brevundimonas kwangchunensis sp. nov., isolated from an alkaline soil in Korea

2006 ◽  
Vol 56 (3) ◽  
pp. 613-617 ◽  
Author(s):  
Jung-Hoon Yoon ◽  
So-Jung Kang ◽  
Hyun Woo Oh ◽  
Jung-Sook Lee ◽  
Tae-Kwang Oh
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Phylogenetic Trees ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
Alkaline Soil ◽  
Bacterial Strains ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Dna Relatedness

Two Gram-negative, rod-shaped bacterial strains, KSL-102T and KSL-110, were isolated from an alkaline soil in Korea, and their taxonomic positions were investigated by use of a polyphasic study. The two strains grew optimally at pH 7·0–8·0 and 30 °C without NaCl. They contained Q-10 as the predominant ubiquinone. The major fatty acids were C18 : 1 ω7c and C16 : 0 on trypticase soy agar, but 11-methyl C18 : 1 ω7c was also a major component when the two strains were cultivated on LMG medium no. 221. Their DNA G+C contents were 68·4–68·7 mol%. Strains KSL-102T and KSL-110 exhibited three nucleotide differences in their 16S rRNA gene sequences and a mean DNA–DNA relatedness value of 85 %. Phylogenetic trees based on 16S rRNA gene sequences showed that the two strains fell within the evolutionary radiation encompassed by the genus Brevundimonas. Levels of 16S rRNA gene sequence similarity between the two strains and the type strains of recognized Brevundimonas species ranged from 96·3 to 98·4 %. DNA–DNA relatedness levels between the two strains and recognized Brevundimonas species were 8–21 %. On the basis of phenotypic, phylogenetic and genetic data, strains KSL-102T and KSL-110 were classified in the genus Brevundimonas as members of a novel species, for which the name Brevundimonas kwangchunensis sp. nov. is proposed. The type strain is KSL-102T (=KCTC 12380T=DSM 17033T).

scholarly journals POTENTIAL USE OF ENDOPHYTIC BACTERIA TO CONTROL Pratylenchus brachyurus ON PATCHOULI

2012 ◽  
Vol 13 (2) ◽  
pp. 86
Author(s):  
Rita Harni ◽  
Supramana Supramana ◽  
Supriadi Supriadi
Keyword(s):  
Bacillus Subtilis ◽  
16S Rrna ◽  
Plant Growth ◽  
Bacillus Cereus ◽  
Pseudomonas Putida ◽  
Endophytic Bacteria ◽  
Alcaligenes Faecalis ◽  
Molecular Techniques ◽  
Achromobacter Xylosoxidans ◽  
Pratylenchus Brachyurus

<p>Pratylenchus brachyurus is an important parasitic nematode which significantly decreases quality and quantity of patchouli oil. One potential measure for controlling the nematode is by using endophytic bacteria. These bacteria also induce plant growth. This study aimed to evaluate the potential of endo-phytic bacteria to control P. brachyurus. The experiments were carried out in the Bacteriological Laboratory of the Plant Protection Department, Bogor Agricultural University, and the Laboratory and Greenhouse of the Indonesian Spice and Medicinal Crops Research Institute from April to December 2007. Endophytic bacteria were isolated from the roots of patchouli plants sampled from various locations in West Java. Antagonistic activity of the isolates were selected against P. brachyurus and their abilities to induce plant growth of patch-ouli plants. Isolates having ability to control P. brachyurus and promote plant growth were identified by molecular techniques using 16S rRNA universal primers. The results showed that a total of 257 isolates of endophytic bacteria were obtained from patchouli roots and their population density varied from 2.3 x 102 to 6.0 x 105 cfu g-1 fresh root. As many as 60 isolates (23.34%) were antagonistic against P. brachyurus causing 70-100% mortality of the namatode, 72 isolates (28.01%) stimu-lated plant growth, 32 isolates (12.47%) inhibited plant growth, and 93 isolates (36.18%) were neutral. Based on their antago-nistic and plant growth enhancer characters, five isolates of the bacteria, namely Achromobacter xylosoxidans TT2, Alcaligenes faecalis NJ16, Pseudomonas putida EH11, Bacillus cereus MSK, and Bacillus subtilis NJ57 suppressed 74.0-81.6% nema-tode population and increased 46.97-86.79% plant growth. The study implies that the endophytic bacteria isolated from patchouly roots are good candidates for controlling P. brachyurus on patchouly plants.</p><p> </p><p>Bahasa Indonesia</p><p>Pratylenchus brachyurus adalah nematoda parasit pada tana-man nilam yang dapat menurunkan hasil dan kualitas minyak nilam. Salah satu cara pengendalian yang potensial terhadap nematoda tersebut adalah menggunakan bakteri endofit. Selain dapat membunuh nematoda, bakteri endofit juga dapat meng-induksi pertumbuhan tanaman. Penelitian bertujuan untuk  mengevaluasi potensi bakteri endofit yang berasal dari tanaman nilam untuk mengendalikan namatoda parasit P. brachyurus. Penelitian dilakukan di Laboratorium Bakteriologi, Departemen Proteksi Tanaman, Institut Pertanian Bogor, serta di  laboratorium dan rumah kaca Balai Penelitian Tanaman Rempah dan Obat, pada bulan April sampai Desember 2007. Bakteri endofit diisolasi dari sampel akar tanaman nilam dari beberapa lokasi di Jawa Barat. Isolat-isolat bakteri endofit diseleksi kemampuannya untuk membunuh P. brachyurus dan menginduksi pertumbuhan tanam-an nilam. Isolat bakteri endofit yang potensial selanjutnya diidentifikasi secara molekuler menggunakan primer universal 16S rRNA. Penelitian memperoleh 257 isolat bakteri endofit dengan kerapatan populasi 2,3 x 102 sampai 6,0 x 105  cfu g-1 berat basah akar. Enam puluh isolat (23,34%) di antaranya bersifat antagonis terhadap P. brachyurus dengan mortalitas 70-100%, 72 isolat (28,01%) dapat memacu pertumbuhan tanaman nilam, 93 isolat (36,18%) bersifat netral, dan 32 isolat (12,47%) dapat menghambat pertumbuhan tanaman. Berdasarkan hasil peng-ujian antagonis dan pemacu pertumbuhan tanaman, lima isolat bakteri, yaitu Achromobacter xylosoxidans TT2, Alcaligenes faecalis NJ16,  Pseudomonas putida EH11, Bacillus cereus MSK, dan Bacillus subtilis NJ57 dapat menekan populasi nematoda 74,0-81,6% dan meningkatkan pertumbuhan nilam 46,97-86,79%. Penelitian mengindikasikan bahwa bakteri endofit dari tanaman nilam berpotensi mengendalikan P. brachyurus pada tanaman nilam.<br /><br /></p>

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

2024 ◽  
Vol 84 ◽  
Author(s):  
A. Javaid ◽  
M. Hussain ◽  
K. Aftab ◽  
M. F. Malik ◽  
M. Umar ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Close Relation ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Larval Weight ◽  
Silkworm Larvae ◽  
Cocoon Production ◽  
Isolation And Characterization

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.

Phenotypic and Genotypic Characterizations of Non-Biofilm Producer Porphyromonas gingivalis Associated with Periodontitis in Al-Najaf, Al-Ashraf/Iraq

2019 ◽  
Vol 10 (01) ◽  
Author(s):  
Hiba Redha Hussain ◽  
Ahlam Kadhum Al-Yasseen
Keyword(s):  
16S Rrna ◽  
Porphyromonas Gingivalis ◽  
Virulence Factors ◽  
Bacterial Growth ◽  
Chronic Periodontitis ◽  
Bacterial Strains ◽  
Biofilm Production ◽  
The University ◽  
Holy City

This study aims to investigate the correlation between some virulence factors and biofilm production among Porphyromonas gingivalis associated with periodontitis. One hundred and two sub gingival swabs have been collected from patients suffering from acute and chronic periodontitis admitted to Specialty Dental center in the Holy city of Najaf and specialized clinics in the Faculty of Dentistry of the University of Kufa from both sexes during the period from September 2017 to January 2018. A total of 34 isolates (28.43%) were identified as P. gingivalis by amplification of 16S rRNA using PCR technique. luxS, lux pro and lux down genes were investigated and the results of PCR showed that none of the strains were possess luxS, 3 strains of P. gingivalis were possess lux pro and 2 strains of P. gingivalis were possess lux dwn. Only 10 strains of P. gingivalis were selected for detection of some virulence factors. The results showed that all strains were unable to produce biofilm with variant abilities of bacterial strains for autoaggregation have been observed (decrease in O.D of bacterial growth after 1 hr. of incubation), and one strain gave +ve results for hemagglutination.

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