scholarly journals Bacterial isolates from bryozoan Pleurocodonellina sp.: Diversity and antimicrobial potential against pathogenic bacteria

2019 ◽  
Vol 20 (9) ◽  
Author(s):  
Meezan Ardhanu Asagabaldan ◽  
Gilles Bedoux ◽  
Nathalie Bourgougnon ◽  
Rhesi Kristiana ◽  
Diah Ayuningrum ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
16S Rrna Gene Sequencing ◽  
Antibacterial Activities ◽  
Multidrug Resistant ◽  
Rrna Gene ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Associated Bacteria ◽  
Antimicrobial Potential ◽  
Rrna Gene Sequencing

Abstract. Asagabaldan MA, Bedoux G, Bourgougnon N, Kristiana R, Ayuningrum D, Sabdono A, Trianto A, Radjasa OK. 2019. Bacterial isolates from bryozoan Pleurocodonellina sp.: Diversity and antimicrobial potential against pathogenic bacteria. Biodiversitas 20: 2528-2535.  There is an urgent need to discover new compounds with antibacterial activity, which can be developed into lead structures for the treatment of human disease caused by multidrug-resistant (MDR) bacteria. In this study, we focussed on bryozoan-associated bacteria to screen them toward antibacterial activities, since the microbiome of these organisms can still be regarded as under-investigated. Most of the few publications about bryozoan-associated bacteria focused on taxonomy and the potential as producers of antibacterial natural products were neglected. Four specimens of bryozoan Pleurocodonellina sp. were collected from Teluk Awur, Jepara in Java Sea, Indonesia. Therefrom, 56 bacterial strains were isolated, and 17 displayed antibacterial activities against MDR bacteria Pseudomonas aruginosa, Klebsiella pneumoniae, Acinetobacter baumannii, Enterobacter cloacae, and methicillin-resistant Staphylococcus aureus (MRSA). Taxonomic identification of the bacteria by 16S rRNA gene sequencing revealed them belonging to the genera Virgibacillus, Pseudoalteromonas, Halomonas, and Bacillus. Most interestingly, the genus Virgibacillus was dominantly obtained from the Pleurocodonellina sp. specimens, i.e., 12 active isolates. Nevertheless, the best activities against MDR bacteria (both Gram-positive and Gram-negative) were contributed to isolates showing >99% identity to Pseudoalteromonas. The results further suggest adding the genus Virgibacillus as bacteria associated with bryozoan, since to the best of our knowledge there were no reports of this genus isolated from bryozoan.

scholarly journals Characterization of Biosurfactant From Pseudomonas Stutzeri SJ3 for Remediation of Crude Oil-Contaminated Soil

2021 ◽  
Author(s):  
Sekar Harikrishnan ◽  
Singaram Jayalakshmi ◽  
Mohamad S. Alsalhi ◽  
Alager Kartick ◽  
Sandhanasamy Devanesan ◽  
...  
Keyword(s):  
Pseudomonas Stutzeri ◽  
16S Rrna Gene Sequencing ◽  
Antibacterial Activities ◽  
Biosurfactant Production ◽  
Screening Methods ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Emulsification Index ◽  
Work Production ◽  
Rrna Gene Sequencing

Abstract In the present work, production of biosurfactant was studied from the bacterial strains isolated from the soil samples collected from oil contaminated sites in Karaikal ONGC, Puducherry, India. Six morphologically different hydrocarbonoclastic bacterial strains (SJ1-SJ6) isolated on oil agar plates were further screened for biosurfactant production. Based on the screening methods results of 26 mm oil displacement zone, positive results of drop collapse test, 68.14% emulsification index (E24) and 79.2% of bacterial adherence percentage, the isolate SJ3 was selected as the most potent strain and it was identified as P. stutzeri using standard biochemical and 16S rRNA gene sequencing-based methods. Optimization of the P. stutzeri strain showed 36 h incubation, 150 rpm agitation, pH 7.5, 37oC, 1% salinity, 2% glucose as carbon source and 1% yeast extract as nitrogen source were the ideal conditions for growth and the biosurfactant production was found to be growth dependent. The crude biosurfactant showed broad range of antibacterial activity against the bacterial pathogens tested. The P. stutzeri isolated from oil spill site showed biosurfactant with antibacterial activities.

scholarly journals Identification and Genomic Characterization of Pathogenic Bacillus altitudinis from Common Pear Trees in Morocco

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1344
Author(s):  
Naima Lemjiber ◽  
Khalid Naamani ◽  
Annabelle Merieau ◽  
Abdelhi Dihazi ◽  
Nawal Zhar ◽  
...  
Keyword(s):  
16S Rrna Gene Sequencing ◽  
Genomic Islands ◽  
Rrna Gene ◽  
In Planta ◽  
Bacterial Strains ◽  
Bacillus Altitudinis ◽  
Genes Encoding ◽  
Bacillus Spp ◽  
Pear Trees ◽  
Rrna Gene Sequencing

Bacterial burn is one of the major diseases affecting pear trees worldwide, with serious impacts on producers and economy. In Morocco, several pear trees (Pyrus communis) have shown leaf burns since 2015. To characterize the causal agent of this disease, we isolated fourteen bacterial strains from different parts of symptomatic pear trees (leaves, shoots, fruits and flowers) that were tested in planta for their pathogenicity on Louise bonne and Williams cultivars. The results showed necrotic lesions with a significant severity range from 47.63 to 57.77% on leaves of the Louise bonne cultivar inoculated with isolate B10, while the other bacterial isolates did not induce any disease symptom. 16S rRNA gene sequencing did not allow robust taxonomic discrimination of the incriminated isolate. Thus, we conducted whole-genome sequencing (WGS) and phylogenetic analyzes based on gyrA, gyrB and cdaA gene sequences, indicating that this isolate belongs to the Bacillus altitudinis species. This taxonomic classification was further confirmed by the Average Nucleotide Identity (ANI) and the in silico DNA-DNA hybridization (isDDH) analyzes compared to sixty-five Bacillus spp. type strains. The genome was mined for genes encoding carbohydrate-active enzymes (CAZymes) known to play a role in the vegetal tissue degradation. 177 candidates with functions that may support the in planta phytopathogenicity results were identified. To the best of our knowledge, this is the first data reporting B. altitudinis as agent of leaf burn in P. communis in Morocco. Our dataset will improve our knowledge on spread and pathogenicity of B. altitudinis genotypes that appears as emergent phytopathogenic agent, unveiling virulence factors and their genomic location (i.e., within genomic islands or the accessory genome) to induce trees disease.

scholarly journals Xylanolytic Psychotrophs From Andosolic Sedge Fens and Moss Heaths in Iceland

Fine Focus ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. 171-186
Author(s):  
Olivia J. Rickman ◽  
M. Auður Sigurbjörnsdóttir ◽  
Oddur Vilhemsson
Keyword(s):  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Cold Environments ◽  
Specific Pcr ◽  
Xylanolytic Activity ◽  
Cold Active ◽  
Rrna Gene Sequencing ◽  
Stenotrophomonas Rhizophila

Nine xylanolytic bacterial strains were isolated from fen and heath soils in northern Iceland. They were found by 16S rRNA gene sequencing to belong to the genera Paenibacillus, Bacillus, Pseudomonas, and Stenotrophomonas. Using a simple, plate-based semiquantitative assay with azo-crosslinked xylan as the substrate, it was determined that although isolated from cold environments, most of the strains displayed greater xylanolytic activity under mesophilic conditions, with only the paenibacilli displaying markedly cold-active xylanolytic activity. Indeed, for one isolate, Paenibacillus castaneae OV2122, xylanolytic activity was only detected at 15°C and below under the conditions tested. Of the nine strains, Paenibacillus amylolyticus OV2121 displayed the greatest activity at 5°C. Glycohydrolase family-specific PCR indicated that the paenibacilli produced multiple xylanases of families 10 and 11, whereas a family 8 xylanase was detected in Pseudomonas kilonensis AL1515, and a family 11 xylanase in Stenotrophomonas rhizophila AL1610.

Characterization of bacteria and antibiotic resistance in commercially-produced cheeses sold in China

2021 ◽  
Author(s):  
Jinghui Yao ◽  
Jing Gao ◽  
Jianming Guo ◽  
Hengan Wang ◽  
En Zhang ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Acquired Resistance ◽  
Antibiotic Resistance Genes ◽  
16S Rrna Gene Sequencing ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

The consumption of cheese in China is increasing rapidly. Little is known about the microbiota, the presence of antibiotic-resistant bacteria, or the distribution of antibiotic resistance genes (ARGs) in commercially-produced cheeses sold in China. These are important criteria for evaluating quality and safety. Thus, this study assessed the metagenomics of fifteen types of cheese using 16S rRNA gene sequencing. Fourteen bacterial genera were detected. Lactococcus , Lactobacillus , and Streptococcus were dominant based on numbers of sequence reads. Multidrug-resistant lactic acid bacteria were isolated from most of the types of cheese. The isolates showed 100% and 91.7% resistance to streptomycin and sulfamethoxazole, respectively, and genes involved in acquired resistance to streptomycin ( strB) and sulfonamides ( sul2) were detected with high frequency. To analyze the distribution of ARGs in the cheeses in overall, 309 ARGs from eight categories of ARG and nine transposase genes were profiled. A total of 169 ARGs were detected in the 15 cheeses; their occurrence and abundance varied significantly between cheeses. Our study demonstrates that there is various diversity of the bacteria and ARGs in cheeses sold in China. The risks associated with multidrug resistance of dominant lactic acid bacteria are of great concern.

Mechanism of boron tolerance in soil bacteria

2010 ◽  
Vol 56 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Iftikhar Ahmed ◽  
Toru Fujiwara
Keyword(s):  
Soil Bacteria ◽  
Gene Sequencing ◽  
16S Rrna Gene Sequencing ◽  
Soil Samples ◽  
Rrna Gene ◽  
Bacterial Strains ◽  
Tolerance Mechanisms ◽  
Boron Tolerance ◽  
Rrna Gene Sequencing ◽  
Comparative Phylogenetic Analysis

Boron (B) is toxic to living cells at levels above a certain threshold. We isolated several B-tolerant bacterial strains from soil samples and studied them for possible mechanisms of B tolerance. 16S rRNA gene sequencing and comparative phylogenetic analysis demonstrated that the isolates belong to the following 6 genera: Arthrobacter , Rhodococcus , Lysinibacillus , Algoriphagus , Gracilibacillus , and Bacillus . These isolates exhibited B-tolerance levels of 80, 100, 150, 300, 450, and 450 mmol/L, respectively, whilst maintaining a significantly lower intracellular B concentration than in the medium. Statistical analysis showed a negative correlation between the protoplasmic B concentration and the degree of tolerance to a high external B concentration. The kinetic assays suggest that the high B efflux and (or) exclusion are the tolerance mechanisms against a high external B concentration in the isolated bacteria.

scholarly journals Antimicrobial activity of bacteria isolated from tissue of the coral Palythoa caribaeorum (Zoantharia: Sphenopidae) from Paraíba, Brazil coastal reefs

2021 ◽  
Vol 69 (2) ◽  
Author(s):  
Jalcinês C. Pereira ◽  
Krystyna Gorlach-Lira ◽  
Bruno O. de Veras
Keyword(s):  
Antimicrobial Activity ◽  
Culture Cell ◽  
Rrna Gene ◽  
Bacterial Isolates ◽  
Bacterial Strains ◽  
Associated Bacteria ◽  
Microdilution Method ◽  
Palythoa Caribaeorum ◽  
Bacillus Genus ◽  
Low Cytotoxicity

Introduction: The coral-associated bacteria with antimicrobial activity may be important to promote the health of their host through various interactions, and may be explored as a source of new bioactive compounds. Objective: To analyze the antimicrobial activity of bacteria associated with the zoanthid Palythoa caribaeorum from the coral reefs of Carapibus, Paraiba state, Brazil. Methods: The phylogenetic analysis of the bacteria was conducted based on partial sequences of the 16S rRNA gene using molecular and bioinformatics tools. The antimicrobial activity of the 49 isolates was tested against four bacterial strains and one yeast strain: Bacillus cereus (CCT0198), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa and Candida albicans (ATCC 10231). The antibiosis and antibiogram assays were conducted and the Minimal Inhibitory Concentration (MIC) was determined by the microdilution method. Results: The bacterial isolates belonged to Firmicutes phylum (84 % of the isolates) and the Proteobacteria phylum (16 % of the isolates). Among the 49 isolates five genera were found, with the Bacillus genus being the most abundant (82 % of the isolates), followed by Vibrio (10 %), Pseudomonas (4 %), Staphylococcus (2 %) and Alteromonas (2 %). Antibiosis test revealed that 16 isolates (33 %) showed antimicrobial activity against one or more of five tested reference strains. The highest number of antagonistic bacteria were found in the Bacillus genus (12 isolates), followed by Vibrio (three isolates) and Pseudomonas (one isolate) genera. The B. subtilis NC8 was the only isolate that inhibited all tested strains in the antibiosis assay. However, antibiogram test with post-culture cell-free supernatant of NC8 isolate showed the inhibition of only B. cereus, S. aureus and C. albicans, and the lyophilized and dialyzed material of this isolate inhibited only B. cereus. The lyophilized material showed bacteriostatic activity against B. cereus, with a MIC value of 125 μg/μl, and in the cytotoxicity assay, the hemolysis value was of 4.8 %, indicating its low cytotoxicity. Conclusions: The results show the antimicrobial potential of some bacterial isolates associated with the P. caribaeourum tissue, especially those belonged to Bacillus genus.

scholarly journals Assessment and Characterization of Xylanolytic Bacteria Isolated from the Gut of Microtermes Obesi for Biomass Pretreatment

2021 ◽  
Author(s):  
Iram Batool ◽  
Falak Sher Khan ◽  
Muhammad Awais ◽  
Dawood Ahmed ◽  
Sami Ullah Khan ◽  
...  
Keyword(s):  
Corn Stover ◽  
Rice Straw ◽  
16S Rrna Gene Sequencing ◽  
Major Constituent ◽  
Rrna Gene ◽  
Bacterial Isolates ◽  
Cotton Stalk ◽  
Termite Gut ◽  
Chemical Pretreatments ◽  
Rrna Gene Sequencing

Abstract The aim of current research was to examine the potential for the production of hemicelluloses degrading enzymes from bacteria harbor in termite gut. The research was also focused on the conversion of lignocellulosic biomass (Corn stover, rice straw and cotton stalk) into fermentable sugars by using enzymes from the bacterial isolates. The bacterial isolates from termite gut were screened for their ability to degrade xylan that is the major constituent of hemicelluloses. Two bacterial isolates were chosen and identified by 16S rRNA gene sequencing. Both isolates TGB9 and TGB10 belong to Bacillus geneus. The isolates have shown higher xylan degrading activity at 50 oC and optimum pH was 6.0. Xylanases from isolate TGB9 and TGB10 were utilized for sccharification of agricultural substrates (stover, rice straw and cotton stalk). As a result higher contents of reducing sugars were observed from corn stover. Xylanases from isolate TGB9 produced higher yields of reducing sugar than isolate TGB10. A comparative study was also performed among chemical pretreatment and xylanases from bacterial isolates. For this purpose agricultural substrates were also treated with H2SO4 and NaOH. Xylanases produced by TGB9 and TGB10 released higher content of sugar from agricultural substrates than chemical pretreatments. So it is concluded that termite gut have bacteria that can hydrolyze hemicelluloses more efficiently than chemicals.

scholarly journals Characterization of Lactic Bacteria Isolated from Raw Milk and Their Antibacterial Activity against Bacteria as the Cause of Clinical Bovine Mastitis

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Nada K. Alharbi ◽  
Albandary Nasser Alsaloom
Keyword(s):  
Bovine Mastitis ◽  
16S Rrna Gene Sequencing ◽  
Raw Milk ◽  
Antibacterial Activities ◽  
Antagonistic Activity ◽  
23S Rrna ◽  
Rrna Gene ◽  
Technological Properties ◽  
23S Rrna Gene ◽  
Rrna Gene Sequencing

The objectives of this study were the selection of lactic acid bacteria (LAB) isolated from raw milk and studying their technological properties and antibacterial activities against bacteria as the cause of cattle mastitis. Biochemical and molecular identification using 16S–23S rRNA gene spacer analysis and 16S rRNA gene sequencing highlighted the presence of three species: Lactiplantibacillus plantarum, Lactococcus lactis, and Levilactobacillus brevis. The enzymatic characterization followed by the determination of technofunctional properties showed that LAB strains did not exhibit any hemolytic effect and were able to produce protease and lipase enzymes. Isolates showed very high antagonistic activity against Gram-positive and Gram-negative bacteria by producing H2O2, bacteriocin(s), and organic acid(s). APIZYM micromethod demonstrated that all selected strains are capable of producing valine arylamidase, cystine arylamidase, N-acetyl-β-glucosaminidase, and ᾳ-mannosidase. The antibiotic susceptibility assay showed that all selected strains were sensible to the majority of tested antibiotics. Based on these results, it can be concluded that the technological properties of the selected LAB allow considering their industrial use in order to formulate bioactive functional foods or drug(s).

scholarly journals Effects of Probiotic Bacteria Lactobacillaceae on the Gut Microbiota in Children With Celiac Disease Autoimmunity: A Placebo-Controlled and Randomized Clinical Trial

2021 ◽  
Vol 8 ◽  
Author(s):  
Elin Oscarsson ◽  
Åsa Håkansson ◽  
Carin Andrén Aronsson ◽  
Göran Molin ◽  
Daniel Agardh
Keyword(s):  
Celiac Disease ◽  
Gut Microbiota ◽  
Tissue Transglutaminase ◽  
16S Rrna Gene Sequencing ◽  
Probiotic Bacteria ◽  
Rrna Gene ◽  
Sequence Variant ◽  
Bacterial Strains ◽  
Probiotic Supplementation ◽  
Rrna Gene Sequencing

Disturbances of the gut microbiota may influence the development of various autoimmune diseases. This study investigated the effects of supplementations with the probiotic bacteria, Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2, on the microbial community in children with celiac disease autoimmunity (CDA). The study included 78 genetically predisposed children for celiac disease with elevated levels of tissue transglutaminase autoantibodies (tTGA) signaling for ongoing CDA. Among those children, 38 received a placebo and 40 received the probiotic supplement daily for 6 months. Fecal and plasma samples were collected at baseline and after 3 and 6 months, respectively. The bacterial community was investigated with 16S rRNA gene sequencing and terminal restriction fragment length polymorphism (T-RFLP), and tTGA levels were measured in radiobinding assays. In children that received probiotic supplementation, the relative abundance of Lactobacillaceae increased over time, while it remained unchanged in the placebo group. There was no overall correlation between tTGA levels and bacterial genus except for a positive correlation between Dialister and IgG-tTG in the probiotic group. The abundance of specific bacterial amplicon sequence variant (ASV:s) changed during the study in both groups, indicating that specific bacterial strains might be affected by probiotic supplementation.

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