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3 Biotech Mar 2022Production of biosurfactant by a novel indigenous isolate strain DU13 and its role in bioremediation of petroleum hydrocarbon is reported. The identity of the isolate...
Production of biosurfactant by a novel indigenous isolate strain DU13 and its role in bioremediation of petroleum hydrocarbon is reported. The identity of the isolate was confirmed by 16S rDNA gene sequencing analysis (Genbank accession: MK177190). The biosurfactant produced by the isolate could reduce the surface tension of petroleum supplemented medium by 46% just after 7 days of treatment. The emulsification index ( ) of the surfactant was found 37, 35, and 20%, respectively, against used motor oil, diesel, and kerosene. The FTIR spectrum of the crude biosurfactant showed the presence of υ stretch, υ υ stretch and υ bonding. The isolated strain could degrade 26% of TPH content of used motor oil in liquid culture. Whereas, ex situ pilot-scale field trial demonstrated very high bioremediation potential of the isolate in terms of germination rate of and seeds and plant growth just after 20 days of treatment.
PubMed: 35223354
DOI: 10.1007/s13205-022-03133-2 -
Biologia 2022Aquaculture is a highly productive and fast-growing agricultural sector. The occurrence of epidemic or sporadic disease outbreak is a major limiting factor in this...
Aquaculture is a highly productive and fast-growing agricultural sector. The occurrence of epidemic or sporadic disease outbreak is a major limiting factor in this sector, thus better alternatives are the need of the hour. Use of indigenous probiotics is a promising strategy to control infectious diseases. Thus, the present study was aimed to screen and characterize potent indigenous probiotics from marine fish, towards enhancing sustainable aquaculture production. Totally 347 bacterial isolates were obtained from gastrointestinal tract, out of these, four isolates (KAF121, 124, 135, 136) were confirmed as potent probiotics in terms of biosafety, highly resistant to acidic pH, gastric juice, bile salt, high hydrophobicity to solvents, auto and co-aggregation potential. These four isolates also exhibited virtuous antioxidant activity. Further the isolates, KAF124 and 135 proved their efficiency in growth and survival of fish after challenged againt . The isolates were identified based on their 16S rRNA gene sequence and the data were submitted to Genbank as KAF121 (MH393516) KAF124 (MH393226) KAF135 (MH393230) and KAF136 (MH393230). The results conclude that two isolates, KAF124 and KAF135 are highly safe and potent probiotics which are first time isolated from the marine fish The two strains could be used as better alternatives to antibiotics and other chemical-based drugs to prevent/control infectious diseases in aquaculture.
PubMed: 35034969
DOI: 10.1007/s11756-021-00957-w -
Biotechnologia 2021Melanin finds enormous applications in different industries for its unique photoprotective and anti-oxidant properties. Due to its emerging demand, scientific...
BACKGROUND
Melanin finds enormous applications in different industries for its unique photoprotective and anti-oxidant properties. Due to its emerging demand, scientific researchers are putting efforts to unravel more microorganisms with a potential of producing melanin on large scale. Hence, the present study was aimed at the isolation of extracellular melanin producing microorganisms from lime quarries of Karnataka, India. Besides this, the tyrosinase gene governing melanin synthesis in different organisms were compared to understand its evolutionary aspects.
MATERIAL AND METHODS
Melanin producing microorganisms were screened on tyrosine gelatin beef extract agar medium. Potential isolate was explored for submerged production of melanin in broth containing L-tyrosine. Melanin was characterized by UV-Vis spectroscopy, thin layer and high performance liquid chromatographic techniques. Antibacterial activity of melanin was performed by agar well assay. Comparative tyrosinase gene sequence analysis was performed by using Geneious 2021.1 trial version software.
RESULTS
DDB2 was found to be potential for melanin production. No antibacterial activity was exerted by the melanin against tested pathogens. The studies showed that the common central domain of tyrosinase protein sequence of selected sps. exhibited 100% identity with the common central domain of tyrosinase (NP_000363.1).
CONCLUSIONS
Our study shows the production of melanin in good quantities by the isolate DDB2 which can be explored for scale-up process. Since the melanin formed is of eumelanin type and the tyrosinase gene sequence of several sp. showed relatedness to humans, this molecule may be further developed for sunscreen formulations.
PubMed: 36605604
DOI: 10.5114/bta.2021.111106 -
International Journal of Systematic and... Nov 2021Strain TUM18999 was isolated from the skin of a patient with burn wounds in Japan. The strain was successfully cultured at 20-42 °C (optimum, 30-35 °C) in 1.0-4.0%...
Strain TUM18999 was isolated from the skin of a patient with burn wounds in Japan. The strain was successfully cultured at 20-42 °C (optimum, 30-35 °C) in 1.0-4.0% NaCl (w/v) and at pH 5.5-9.5, optimum pH 5.5-8.5. The phylogenetic tree reconstructed using 16S rRNA, , and gene sequences indicated that strain TUM18999 is closely related to MCC10330. Although the partial 16S rRNA gene sequence (1412 bp) of TUM18999 exhibits high similarity to those of NBRC 14159 (99.08 %) and MCC10330 (98.51 %), multi-locus sequence analysis using 16S rRNA, , and genes reveals a clear distinction between TUM18999 and other species. In addition, an average nucleotide identity >90 % was not observed in the group. Moreover, TUM18999 and can be distinguished based on the minimum inhibitory concentration for carbapenem. Meanwhile, the cellular fatty acids are enriched with C 7/C 6 (34.35 %), C 7/C 6 (24.22 %), C (19.79 %) and C (8.25 %). Based on this evidence, strain TUM18999 can be defined as representing a novel species, with the proposed name sp. nov. The type strain is TUM18999 (GTC 22698=NCTC 14580).
Topics: Bacterial Typing Techniques; Base Composition; Burns; DNA, Bacterial; Fatty Acids; Genes, Bacterial; Humans; Japan; Phylogeny; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Skin
PubMed: 34762579
DOI: 10.1099/ijsem.0.005115 -
BMC Infectious Diseases Aug 2021Pseudomonas otitidis is a novel species of Pseudomonas bacteria that has been isolated from patients with otic infections. (Review)
Review
BACKGROUND
Pseudomonas otitidis is a novel species of Pseudomonas bacteria that has been isolated from patients with otic infections.
CASE PRESENTATION
In this report, we describe a case of a 59-year-old known with moderate chronic obstructive pulmonary disease with bronchiectasis and recurrent pneumonia where blood cultures revealed the growth of P. otitidis.
CONCLUSIONS
This case describes the first report of bacteraemia to P. otitidis and raises questions regarding the misdiagnosis and underestimation of the incidence of infections caused by this novel pathogen.
Topics: Bacteremia; Humans; Middle Aged; Pneumonia; Pseudomonas; Pulmonary Disease, Chronic Obstructive
PubMed: 34433417
DOI: 10.1186/s12879-021-06569-8 -
Microorganisms Jun 2021The rhizobacterium AVO110 exhibits antagonism toward the phytopathogenic fungus . This strain efficiently colonizes hyphae and is able to feed on their exudates. Here,...
The rhizobacterium AVO110 exhibits antagonism toward the phytopathogenic fungus . This strain efficiently colonizes hyphae and is able to feed on their exudates. Here, we report the complete genome sequence of AVO110. The phylogeny of all available genomes separates environmental isolates, including AVO110, from those obtained from infected human blood and oyster tissues, which cluster together with . Core and pan-genome analyses showed that strains encode highly heterogenic gene pools, with the AVO110 genome encoding the largest and most exclusive variable region (~1.6 Mb, 1795 genes). The AVO110 singletons include a wide repertoire of genes related to biofilm formation, several of which are transcriptionally modulated by exudates. One of these genes () encodes a GGDEF/EAL domain protein specific to spp. strains isolated primarily from the rhizosphere of diverse plants, but also from soil and water samples. We also show that CmpA has a role in biofilm formation and that the integrity of its EAL domain is involved in this function. This study contributes to a better understanding of the niche-specific adaptations and lifestyles of , including the mycophagous behavior of strain AVO110.
PubMed: 34202389
DOI: 10.3390/microorganisms9071388 -
Environmental Pollution (Barking, Essex... Sep 2021The bioaerosols present in indoor air play a major role in the transmission of infectious diseases to humans, therefore concern about their exposure is increased...
The bioaerosols present in indoor air play a major role in the transmission of infectious diseases to humans, therefore concern about their exposure is increased recently. In this regard, the present investigation described the preparation of lemongrass essential oil (LGEO) loaded chitosan and cellulose nanofibers composites (CH/CNF) for controlling the indoor air bioaerosol. The evaluation of the inhibitory effect of the composite system on culturable bacteria of the indoor air was done at different sites (air volume from 30 m to 80 m) and in different size fractions of aerosol (<0.25 μm-2.5 μm). The composite system had high encapsulation efficiency (88-91%) and citrals content. A significant reduction in culturable bacteria of aerosol (from 6.23 log CFUm to 2.33 log CFUm) was observed in presence of cellulose nanofibers and chitosan composites. The bacterial strains such as Staphylococcus sp., Bacillus cereus, Bacillus pseudomycoides sp., Pseudomonas otitidis, and Pseudomonas sp. Cf0-3 in bioaerosols were inhibited dominantly due to the diffusion of aroma molecules in indoor air. The results indicate that the interaction of diffused aroma molecule from the composite system with bacterial strains enhanced the production of ROS, resulting in loss of membrane integrity of bacterial cells. Among different size fractions of aerosol, the composite system was more effective in finer size fractions (<0.25 μm) of aerosol due to the interaction of smaller aroma compounds with bacterial cells. The study revealed that LGEO loaded chitosan and cellulose nanofibers composites could be a good option for controlling the culturable bacteria even in small-sized respirable bioaerosol.
Topics: Aerosols; Air Microbiology; Air Pollution, Indoor; Bacillus; Chitosan; Humans; Oils, Volatile; Plant Oils; Pseudomonas; Terpenes
PubMed: 34049138
DOI: 10.1016/j.envpol.2021.117407 -
Frontiers in Microbiology 2020Anthropogenic perturbations introduce novel selective pressures to natural environments, impacting the genomic variability of organisms and thus altering the...
Anthropogenic perturbations introduce novel selective pressures to natural environments, impacting the genomic variability of organisms and thus altering the evolutionary trajectory of populations. Water overexploitation for agricultural purposes and defective policies in Cuatro Cienegas, Coahuila, Mexico, have strongly impacted its water reservoir, pushing entire hydrological systems to the brink of extinction along with their native populations. Here, we studied the effects of continuous water overexploitation on an environmental aquatic lineage of over a 13-year period which encompasses three desiccation events. By comparing the genomes of a population sample from 2003 (original state) and 2015 (perturbed state), we analyzed the demographic history and evolutionary response to perturbation of this lineage. Through coalescent simulations, we obtained a demographic model of contraction-expansion-contraction which points to the occurrence of an evolutionary rescue event. Loss of genomic and nucleotide variation alongside an increment in mean and variance of Tajima's , characteristic of sudden population expansions, support this observation. In addition, a significant increase in recombination rate (R/θ) was observed, pointing to horizontal gene transfer playing a role in population recovery. Furthermore, the gain of phosphorylation, DNA recombination, small-molecule metabolism and transport and loss of biosynthetic and regulatory genes suggest a functional shift in response to the environmental perturbation. Despite subsequent sampling events in the studied site, no pseudomonad was found until the lagoon completely dried in 2017. We speculate about the causes of final decline or possible extinction. Overall our results are evidence of adaptive responses at the genomic level of bacterial populations in a heavily exploited aquifer.
PubMed: 33552002
DOI: 10.3389/fmicb.2020.563885 -
Pathogens (Basel, Switzerland) Feb 2021causes deadly primary amoebic meningoencephalitis (PAM) in humans. Humans obtain the infection by inhaling water or dust contaminated with amebae into the nostrils,...
causes deadly primary amoebic meningoencephalitis (PAM) in humans. Humans obtain the infection by inhaling water or dust contaminated with amebae into the nostrils, wherefrom the pathogen migrates via the olfactory nerve to cause brain inflammation and necrosis. Current PAM treatment is ineffective and toxic. Seeking new effective and less toxic drugs for the environmental control of the amoeba population to reduce human exposure is logical for the management of infection. On the basis of the concept of competitive exclusion, where environmental microorganisms compete for resources by secreting factors detrimental to other organisms, we tested cell-free culture supernatants (CFSs) of three bacteria isolated from a fresh water canal, i.e., , , and , were tested against . The CFSs inhibited growth and caused morphological changes in . At low dose, trophozoites exposed to pyocyanin were seen to shrink and become rounded, while at high dose, the trophozoites were fragmented. While the precise molecular mechanisms of pyocyanin and products of and that also exert anti- activity await clarification. Our findings suggest that pyocyanin may have a role in the control of amphizoic in the environment.
PubMed: 33535404
DOI: 10.3390/pathogens10020142 -
International Journal of Environmental... Jan 2021Recently, the application of endophytes in the alleviation of different types of stresses has received considerable attention, but their role in drought stress...
Recently, the application of endophytes in the alleviation of different types of stresses has received considerable attention, but their role in drought stress alleviation and growth promotion in soybean is not well-stated. In this study, twenty bacterial endophytes were isolated from soybean root tissues and screened for plant growth-promoting (PGP) traits, biocontrol potential, and drought stress alleviation. Out of them, 80% showed PGP traits, and 20% showed antagonistic activity against (ITCC 2389), (ITCC 1800), and (ITCC 3467), and only three of them showed drought tolerance up to 15% (-0.3 MPa). Results indicated that drought-tolerant PGP endophytic bacteria enhanced soybean seedling growth under drought stress conditions. Morphological, biochemical, and molecular characterization (16S rRNA) revealed that these three bacterial isolates, AKAD A1-1, AKAD A1-2, and AKAD A1-16, closely resemble (GenBank accession No. MN079048), (MW301101), and sp. (MN079074), respectively. We observed that the soybean seedlings were grown in well-watered and drought-stressed soil showed the adverse effect of drought stress on morphological (stem length, root length, plant fresh and dry weight) as well as on biochemical parameters (a decline of photosynthetic pigments, membrane damage, etc.). However, soybean seedlings inoculated with these endophytes have improved the biomass significantly ( ≤ 0.05) under normal as well as in drought stress conditions over control treatments by influencing several biochemical changes. Among these three endophytes, AKAD A1-16 performed better than AKAD A1-2 and AKAD A1-1, which was further validated by the ability to produce the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase in the following order: AKAD A1-16 > AKAD A1-2 > AKAD A1-1. Scanning electron microscopy images also showed a bacterial presence inside the roots of soybean seedlings. These findings supported the application of bacterial root endophytes as a potential tool to mitigate the effect of drought as well as of fungal diseases on the early seedling growth of soybean.
Topics: Alternaria; Ascomycota; Bacteria; Droughts; Endophytes; Fusarium; Plant Roots; Pseudomonas; RNA, Ribosomal, 16S; Glycine max
PubMed: 33494513
DOI: 10.3390/ijerph18030931