Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 46
Filter
Add more filters










Publication year range
1.
PLoS One ; 19(5): e0304061, 2024.
Article in English | MEDLINE | ID: mdl-38787843

ABSTRACT

Erosion poses a significant threat to oceanic beaches worldwide. To combat this threat, management agencies often utilize renourishment, which supplements eroded beaches with offsite sand. This process can alter the physical characteristics of the beach and can influence the presence and abundance of microbial communities. In this study, we examined how an oceanic beach renourishment project may have impacted the presence and abundance of Escherichia coli (E. coli), a common bacteria species, and sand grain size, a sediment characteristic that can influence bacterial persistence. Using an observational field approach, we quantified the presence and abundance of E. coli in sand (from sub-tidal, intertidal, and dune zones on the beach) and water samples at study sites in both renourished and non-renourished sections of Folly Beach, South Carolina, USA in 2014 and 2015. In addition, we also measured how renourishment may have impacted sand grain size by quantifying the relative frequency of grain sizes (from sub-tidal, intertidal, and dune zones on the beach) at both renourished and non-renourished sites. Using this approach, we found that E. coli was present in sand samples in all zones of the beach and at each of our study sites in both years of sampling but never in water samples. Additionally, we found that in comparison to non-renourished sections, renourished sites had significantly higher abundances of E. coli and coarser sand grains in the intertidal zone, which is where renourished sand is typically placed. However, these differences were only present in 2014 and were not detected when we resampled the study sites in 2015. Collectively, our findings show that E. coli can be commonly found in this sandy beach microbial community. In addition, our results suggest that renourishment has the potential to alter both the physical structure of the beach and the microbial community but that these impacts may be short-lived.


Subject(s)
Bathing Beaches , Escherichia coli , Escherichia coli/isolation & purification , Water Microbiology , Sand/microbiology , Geologic Sediments/microbiology , South Carolina , Seawater/microbiology
2.
Article in English | MEDLINE | ID: mdl-38787370

ABSTRACT

A Gram-stain-positive, aerobic, non-mobile and spherical strain, designated ZS9-10T, belonging to the genus Deinococcus was isolated from soil sampled at the Chinese Zhong Shan Station, Antarctica. Growth was observed in the presence of 0-4 % (w/v) NaCl, at pH 7.0-8.0 and at 4-25 °C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZS9-10T formed a lineage in the genus Deinococcus. It exhibited highest sequence similarity (97.4 %) to Deinococcus marmoris DSM 12784T. The major phospholipids of ZS9-10T were unidentified phosphoglycolipid, unidentified glycolipids and unidentified lipids. The major fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 0 and C16 : 1 ω7c. MK-8 was the predominant respiratory quinone. The digital DNA-DNA hybridization and average nucleotide identity values between strain ZS9-10T and its close relative D. marmoris DSM 12784T were 27.4 and 83.9 %, respectively. Based on phenotypic, phylogenetic and genotypic data, a novel species, named Deinococcus arenicola sp. nov., is proposed. The type strain iis ZS9-10T (=CCTCC AB 2019392T=KCTC43192T).


Subject(s)
Bacterial Typing Techniques , Base Composition , DNA, Bacterial , Deinococcus , Fatty Acids , Nucleic Acid Hybridization , Phospholipids , Phylogeny , RNA, Ribosomal, 16S , Sequence Analysis, DNA , Soil Microbiology , Antarctic Regions , RNA, Ribosomal, 16S/genetics , Deinococcus/genetics , Deinococcus/classification , Deinococcus/isolation & purification , Fatty Acids/analysis , Fatty Acids/chemistry , DNA, Bacterial/genetics , Phospholipids/analysis , Phospholipids/chemistry , Vitamin K 2/analogs & derivatives , Vitamin K 2/analysis , Vitamin K 2/chemistry , Sand/microbiology
3.
Water Environ Res ; 96(5): e11037, 2024.
Article in English | MEDLINE | ID: mdl-38726833

ABSTRACT

Microbial pollution of recreational waters leads to millions of skin, respiratory, and gastrointestinal illnesses globally. Fecal indicator bacteria (FIB) are monitored to assess recreational waters but may not reflect the presence of Staphylococcus aureus, a global leader in bacterial fatalities. Since many community-acquired S. aureus skin infections are associated with high recreational water usage, this study measured and modeled S. aureus, methicillin-resistant S. aureus (MRSA), and FIB (Enterococcus spp., Clostridium perfringens) concentrations in seawater and sand at six beaches in Hilo, Hawai'i, USA, over 37 sample dates from July 2016 to February 2019 using culturing techniques. Generalized linear models predicted bacterial concentrations with physicochemical and environmental data. Beach visitors were also surveyed on their preferred activities. S. aureus and FIB concentrations were roughly 6-78 times higher at beaches with freshwater discharge than at those without. Seawater concentrations of Enterococcus spp. were positively associated with MRSA but not S. aureus. Elevated S. aureus was associated with lower tidal heights, higher freshwater discharge, onsite sewage disposal system density, and turbidity. Regular monitoring of beaches with freshwater input, utilizing real-time water quality measurements with robust modeling techniques, and raising awareness among recreational water users may mitigate exposure to S. aureus, MRSA, and FIB. PRACTITIONER POINTS: Staphylococcus aureus and fecal bacteria concentrations were higher in seawater and sand at beaches with freshwater discharge. In seawater, Enterococcus spp. positively correlated with MRSA, but not S. aureus. Freshwater discharge, OSDS density, water turbidity, and tides significantly predicted bacterial concentrations in seawater and sand. Predictive bacterial models based upon physicochemical and environmental data developed in this study are readily available for user-friendly application.


Subject(s)
Feces , Seawater , Staphylococcus aureus , Seawater/microbiology , Staphylococcus aureus/isolation & purification , Hawaii , Feces/microbiology , Bathing Beaches , Environmental Monitoring , Sand/microbiology , Water Microbiology , Enterococcus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/isolation & purification
4.
Int Microbiol ; 26(4): 1021-1031, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37076723

ABSTRACT

A Gram-negative, aerobic bacterial strain RR6T was isolated from the sea sand to produce lipase and proposed as a novel species of Halopseudomonas. The optimum growth occurred at 28-37 °C, and the pH was 6.0-8.0. The optimum growth occurred at 3.0 -6.5% (w/v) NaCl. The major cellular fatty acids were C10:0 3OH, C12:0, C16:1 ω7c/16:1 ω6c, 18:1 ω7c and/or 18:1 ω6c, and C16:0. The predominant polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, unidentified phospholipid, and unidentified lipids. The genome is 3.93 Mb, and the G + C content is 61.3%. The 16S rRNA gene sequences shared 99.73-99.87% sequence similarity with the closely related type strains of Halopseudomonas. The average nucleotide identity and average amino acid identity of strain RR6T with reference type strains were below 95-96%, and the corresponding in-silico DNA-DNA hybridization values were below 70%. Strain RR6T clustered with Halopseudomonas gallaeciensis V113T and Halopseudomonas pachastrellae CCUG 46540 T in the phylogenetic tree. Further, lipase produced by this bacterium belongs to α/ß hydrolase lipase family and exhibits structural similarity to the lactonizing lipase. Based on the polyphasic analysis, the new isolates RR6T represent a novel species of Halopseudomonas for which Halopseudomonas maritima sp. nov. is proposed. The type strain is RR6T (= NBRC 115418 T = TBRC 15628 T).


Subject(s)
Lipase , Sand , Sand/microbiology , Phylogeny , RNA, Ribosomal, 16S/genetics , Lipase/genetics , Phospholipids/chemistry , DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques , Sequence Analysis, DNA
5.
FEMS Microbiol Ecol ; 99(5)2023 04 07.
Article in English | MEDLINE | ID: mdl-37019824

ABSTRACT

The water surface microlayer (SML) serves as a boundary through which microbes can be exchanged. To evaluate exchanges of microbes, this study compared microbial communities within different reservoirs, with an emphasis on the water SML and aerosols. Additionally, the microbial communities during a sewage spill and perigean tides were evaluated and the results were compared to times without these events. Results show that during perigean tides and during the sewage spill, levels of culturable bacteria were highest and showed an increase via sequencing in potential pathogenic bacteria (Corynebacterium and Vibrio, which increased from 3.5%-1800% depending on sample type). In the aerosol samples, Corynebacterium (average of 2.0%), Vibrio (1.6%), and Staphylococcus (10%), were the most abundant genera. Aerosolization factors, which were used to examine the transfer of the microbes, were high for these three genera. Measurements of general marine bacteria (GMB) by culture showed a weak but significant correlation between culturable GMB in aerosol samples versus in water and in the SML. More research is needed to evaluate the exchange of pathogens between the SML and air, given the increase in potentially pathogenic microbes within the SML during rare events and evidence that suggests that microbes maintain viability during transfers across reservoirs.


Subject(s)
Aerosols , Air Microbiology , Bathing Beaches , Seawater , Water Microbiology , Aerosols/analysis , Bacteria/isolation & purification , Microbiota , Sand/microbiology , Seawater/microbiology , Sewage/microbiology , Water/analysis
6.
Article in English | MEDLINE | ID: mdl-37022765

ABSTRACT

A novel species of the genus Limimaricola, designated ASW11-118T, was isolated from an intertidal sand sample of the Yellow Sea, PR China. Growth of strain ASW11-118T occurred at 10-40 °C (optimum, 28 °C), pH 5.5-8.5 (optimum, pH 7.5) and with 0.5-8.0 % (w/v) NaCl (optimum, 1.5%). Strain ASW11-118T has the highest 16S rRNA gene sequence similarity to Limimaricola cinnabarinus LL-001T (98.8%) and 98.6 % to Limimaricola hongkongensis DSM 17492T. Phylogenetic analysis based on genomic sequences indicated that strain ASW11-118T belongs to the genus Limimaricola. The genome size of strain ASW11-118T was 3.8 Mb and DNA G+C content was 67.8 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain ASW11-118T and other members of the genus Limimaricola were below 86.6 and 31.3 %, respectively. The predominant respiratory quinone was ubiquinone-10. The predominant cellular fatty acid was C18 : 1 ω7c. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and one unknown aminolipid. On the basis of the data presented, strain ASW11-118T is considered to represent a novel species of the genus Limimaricola, for which the name Limimaricola litoreus sp. nov. is proposed. The type strain is ASW11-118T (=MCCC 1K05581T=KCTC 82494T).


Subject(s)
Phylogeny , Rhodobacteraceae , Sand , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sand/microbiology , Sequence Analysis, DNA , Ubiquinone/chemistry , Rhodobacteraceae/classification , Rhodobacteraceae/isolation & purification
7.
Article in English | MEDLINE | ID: mdl-35805592

ABSTRACT

Beach sand may act as a reservoir for numerous microorganisms, including enteric pathogens. Several of these pathogens originate in human or animal feces, which may pose a public health risk. In August 2019, high levels of fecal indicator bacteria (FIB) were detected in the sand of the Azorean beach Prainha, Terceira Island, Portugal. Remediation measures were promptly implemented, including sand removal and the spraying of chlorine to restore the sand quality. To determine the source of the fecal contamination, during the first campaign, supratidal sand samples were collected from several sites along the beach, followed by microbial source tracking (MST) analyses of Bacteroides marker genes for five animal species, including humans. Some of the sampling sites revealed the presence of marker genes from dogs, seagulls, and ruminants. Making use of the information on biological sources originating partially from dogs, the municipality enforced restrictive measures for dog-walking at the beach. Subsequent sampling campaigns detected low FIB contamination due to the mitigation and remediation measures that were undertaken. This is the first case study where the MST approach was used to determine the contamination sources in the supratidal sand of a coastal beach. Our results show that MST can be an essential tool to determine sources of fecal contamination in the sand. This study shows the importance of holistic management of beaches that should go beyond water quality monitoring for FIB, putting forth evidence for beach sand monitoring.


Subject(s)
Bacteria/isolation & purification , Bathing Beaches/standards , Sand/microbiology , Water Pollution , Animals , Bacteria/classification , Bacteria/genetics , Bacteroides/genetics , Bacteroides/isolation & purification , Charadriiformes , Dogs , Environmental Monitoring/methods , Feces/microbiology , Portugal , Ruminants , Water Microbiology , Water Pollution/analysis
8.
Environ Monit Assess ; 194(6): 448, 2022 May 23.
Article in English | MEDLINE | ID: mdl-35604473

ABSTRACT

Coastal habitats provide important ecosystem services, such as the maintenance of ecological sustainability, water quality regulation, nutrient recycling, and sandy beaches which are important areas for recreation and tourism. The quality of seawater is generally measured by determining the concentrations of Escherichia coli and intestinal Enterococci, which might be affected by the persistent populations of these bacteria in sand. Sand might thus be a significant source of pathogen exposure to beachgoers. The quality of coastal recreational waters can also be affected by eutrophication, water discoloration, and harmful algal blooms, which pose additional human health risks. Here, we conducted a monitoring of the beaches quality along the Taranto Gulf by determining the concentrations of fecal indicator organisms, as well as other parameters that are not traditionally measured (physicochemical parameters, Pseudomonas aeruginosa, and harmful microalgae), in shallow seawater and sand sampled from three beaches. The concentrations of bacteria were determined using both standard microbiological methods and the IDEXX system. Our results demonstrate the utility of measuring a greater number of parameters in addition to those conventionally measured, as well as the importance of assessing the health risks posed by the sand matrix. Additional work is needed to develop rapid analytical techniques that could be used to monitor the microbiological parameters of solid matrices.


Subject(s)
Bathing Beaches , Environmental Monitoring , Sand , Seawater , Bacteria/isolation & purification , Bathing Beaches/standards , Ecosystem , Environmental Monitoring/methods , Escherichia coli/isolation & purification , Humans , Italy , Microalgae/isolation & purification , Sand/chemistry , Sand/microbiology , Seawater/chemistry , Seawater/microbiology , Water Microbiology/standards , Water Quality/standards
9.
Int J Syst Evol Microbiol ; 71(12)2021 Dec.
Article in English | MEDLINE | ID: mdl-34908522

ABSTRACT

A novel Gram-negative, aerobic, non-motile, rod-shaped, bacterial strain (CAU 1598T) was isolated from marine sand. Strain CAU 1598T grew well at 30 °C, pH 6.5-7.0 and with 3 % NaCl (w/v). Phylogeny results based on 16S rRNA gene sequencing indicated that the identified strain had the highest similarity (94.3%) to Pseudoxanthomonas putridarboris, indicating that strain CAU 1598T belongs to the family Xanthomonadaceae. Further, the fatty acid profile of the strain was primarily composed of C16:0, iso-C15 : 0, iso-C16 : 0, summed feature 3 (consisting of C16 : 1 ω7c/iso-C15 : 0 2-OH) and summed feature 9 (consisting of iso-C17 : 1 ω9c and/or C16 : 0 10-methyl), with ubiquinone-8 as the major isoprenoid quinone. The polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphoglycolipid, an unidentified aminolipid and an unidentified lipid. The G+C content of the bacterial genome was 62.6 mol% and its 5.4 Mb length encompassed 144 contigs and 4236 protein-coding genes. These phenotypic, chemotaxonomic and phylogenetic data indicate that CAU 1598T belongs to a new genus and species, for which the name Pseudomarimonas arenosa gen. nov., sp. nov. is proposed. The type strain is CAU 1598T (=KCTC 82406T=MCCC 1K05673T).


Subject(s)
Phylogeny , Sand , Xanthomonadaceae/classification , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sand/microbiology , Seawater , Sequence Analysis, DNA , Ubiquinone/chemistry , Xanthomonadaceae/isolation & purification
10.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Article in English | MEDLINE | ID: mdl-34762580

ABSTRACT

Four yeast isolates with an affinity to the genus Wickerhamiella were obtained from beach sand, a marine zoanthid and a tree exudate at different localities in Brazil. Two other isolates with almost identical ITS and D1/D2 sequences of the large subunit rRNA gene were isolated from the small intestine of cattle and a grease trap in Thailand. These isolates represent a novel species phylogenetically related to Wickerhamiella verensis, Wickerhamiella osmotolerans, Wickerhamiella tropicalis, Wickerhamiella sorbophila and Wickerhamiella infanticola. The novel species differs by 15-30 nucleotide differences from these species in the D1/D2 sequences. The name Wickerhamiella martinezcruziae f.a., sp. nov. is proposed. The holotype of Wickerhamiella martinezcruziae sp. nov. is CBS 16104T. The MycoBank number is MB 839328.


Subject(s)
Phylogeny , Saccharomycetales , Animals , Base Composition , Brazil , Cattle/microbiology , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Intestine, Small/microbiology , Mycological Typing Techniques , Plant Exudates , RNA, Ribosomal, 16S/genetics , Saccharomycetales/classification , Saccharomycetales/isolation & purification , Sand/microbiology , Sequence Analysis, DNA , Thailand , Tropical Climate
11.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Article in English | MEDLINE | ID: mdl-34605765

ABSTRACT

A Gram-stain-negative, aerobic, motile, short rod-shaped, catalase-negative and oxidase-positive bacterium, strain CAU 1568T, was isolated from marine sediment sand sampled at Sido Island in the Republic of Korea. The optimum conditions for growth were at 25-30 °C, at pH 6.5-8.5 and with 0-4.0 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain CAU 1568T was a member of the genus Photobacterium with high similarity to Photobacterium salinisoli JCM 30852T (97.7 %), Photobacterium halotolerans KACC 17089T (97.3 %) and Photobacterium galatheae LMG F28894T (97.3 %). The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), with Q-8 as the major of isoprenoid quinone. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerols, phosphatidylcholine, phosphatidylethanolamine, phospholipid, two aminophospholipids and three unidentified lipids. The whole genome size of strain CAU 1568T was 4.8 Mb with 50.1 mol% G+C content; including 38 contigs and 4233 protein-coding genes. These taxonomic data support CAU 1568T as representing a novel Photobacterium species, for which the name Photobacterium arenosum sp. nov. is proposed. The type strain of this novel species is CAU 1568T (=KCTC 82404T=MCCC 1K05668T).


Subject(s)
Photobacterium , Phylogeny , Sand , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/chemistry , Geologic Sediments/microbiology , Islands , Phospholipids/chemistry , Photobacterium/classification , Photobacterium/isolation & purification , RNA, Ribosomal, 16S/genetics , Republic of Korea , Sand/microbiology , Seawater/microbiology , Sequence Analysis, DNA , Ubiquinone/chemistry
12.
Braz J Microbiol ; 52(4): 2193-2204, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34536217

ABSTRACT

Enzyme activities (EAs) and the FERTBIO sample concept have been increasingly adopted as a novel approach to estimate the soil quality in Brazil. However, the performance of this strategy in sandy soils of the Cerrado biome remains unclear. During 2 years, in a Cerrado's sandy soil, the short-term effects of ten different cropping systems (conventional tillage or no-tillage associated with monoculture, rotations, and/or successions) on the activities of ß-glucosidase, acid phosphatase, and arylsulfatase were studied. Issues related to annual variability and the feasibility of using the FERTBIO sample concept for soil enzymes activities were also evaluated. Soil samples were collected at three different depths (0-10 cm, 10-20 cm, and 20-40 cm) in March 2017 and February 2018. Five years since the beginning of the experiment, the presence of cover crops and no-till promoted improvements in EAs evidencing the importance of regenerative management practices for the sustainability of agroecosystems in sandy soils. Regardless of the cropping systems and depths evaluated, soil organic carbon and EAs showed low temporal variation during the 2 years of monitoring. Our results also showed that it is possible to use the FERTBIO sample concept for the Quartzipsament soils of Western Bahia, Brazil.


Subject(s)
Agriculture , Enzymes , Sand , Soil Microbiology , Brazil , Carbon/analysis , Enzymes/metabolism , Sand/microbiology , Time Factors
13.
Lett Appl Microbiol ; 73(5): 607-615, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34338330

ABSTRACT

The genus Fusarium contains many fungal species known to be pathogenic to animals and plants alike. One species complex within this genus, the Fusarium solani species complex (FSSC), is of particular concern due to its high numbers of pathogenic members. FSSC members are known to contribute significantly to plant, human and other animal fungal disease. One member of the FSSC, Fusarium keratoplasticum, is of particular ecological concern and has been implicated in low hatching success of endangered sea turtle eggs, as well as contribute to human and other animal Fusarium pathogenesis. Species-specific primers for molecular identification of F. keratoplasticum currently do not exist to our knowledge, making rapid identification, tracking and quantitation of this pathogenic fungus difficult. The objective of this study was to develop primers specific to F. keratoplasticum that could be applied to DNA from isolated cultures as well as total (mixed) DNA from environmental samples. RPB2 sequence from 109 Fusarium isolates was aligned and analysed to determine nucleotide polymorphisms specific to F. keratoplasticum useful for primer design. A set of primers were generated and found to be effective for identification of F. keratoplasticum from total DNA extracted from sand surrounding sea turtle nesting sites.


Subject(s)
Fusarium , Sand/microbiology , Animals , DNA Primers , Fusarium/classification , Fusarium/isolation & purification , Polymerase Chain Reaction , Species Specificity , Turtles
14.
PLoS One ; 16(7): e0254676, 2021.
Article in English | MEDLINE | ID: mdl-34270610

ABSTRACT

Microbially Induced Carbonate Precipitation (MICP) is currently viewed as one of the potential prominent processes for field applications towards the prevention of soil erosion, healing cracks in bricks, and groundwater contamination. Typically, the bacteria involved in MICP manipulate their environment leading to calcite precipitation with an enzyme such as urease, causing calcite crystals to form on the surface of grains forming cementation bonds between particles that help in reducing soil permeability and increase overall compressive strength. In this paper, the main focus is to study the MICP performance of three indigenous landfill bacteria against a well-known commercially bought MICP bacteria (Bacillus megaterium) using sand columns. In order to check the viability of the method for potential field conditions, the tests were carried out at slightly less favourable environmental conditions, i.e., at temperatures between 15-17°C and without the addition of urease enzymes. Furthermore, the sand was loose without any compaction to imitate real ground conditions. The results showed that the indigenous bacteria yielded similar permeability reduction (4.79 E-05 to 5.65 E-05) and calcium carbonate formation (14.4-14.7%) to the control bacteria (Bacillus megaterium), which had permeability reduction of 4.56 E-5 and CaCO3 of 13.6%. Also, reasonably good unconfined compressive strengths (160-258 kPa) were noted for the indigenous bacteria samples (160 kPa). SEM and XRD showed the variation of biocrystals formation mainly detected as Calcite and Vaterite. Overall, all of the indigenous bacteria performed slightly better than the control bacteria in strength, permeability, and CaCO3 precipitation. In retrospect, this study provides clear evidence that the indigenous bacteria in such environments can provide similar calcite precipitation potential as well-documented bacteria from cell culture banks. Hence, the idea of MICP field application through biostimulation of indigenous bacteria rather than bioaugmentation can become a reality in the near future.


Subject(s)
Calcium Carbonate/chemistry , Microbiota , Soil Microbiology , Bacillus/metabolism , Calcium Carbonate/metabolism , Chemical Precipitation , Conservation of Natural Resources/methods , Sand/chemistry , Sand/microbiology , Soil/chemistry
15.
Nat Commun ; 12(1): 3037, 2021 05 24.
Article in English | MEDLINE | ID: mdl-34031392

ABSTRACT

Microbialites accrete where environmental conditions and microbial metabolisms promote lithification, commonly through carbonate cementation. On Little Ambergris Cay, Turks and Caicos Islands, microbial mats occur widely in peritidal environments above ooid sand but do not become lithified or preserved. Sediment cores and porewater geochemistry indicated that aerobic respiration and sulfide oxidation inhibit lithification and dissolve calcium carbonate sand despite widespread aragonite precipitation from platform surface waters. Here, we report that in tidally pumped environments, microbial metabolisms can negate the effects of taphonomically-favorable seawater chemistry on carbonate mineral saturation and microbialite development.


Subject(s)
Calcium Compounds/chemistry , Ecosystem , Oxides/chemistry , Sand/chemistry , Sand/microbiology , Calcium Carbonate/metabolism , Carbonates , Geologic Sediments/chemistry , Geologic Sediments/microbiology , Microbiota , Minerals , Seawater/chemistry , Seawater/microbiology , West Indies
16.
BMC Microbiol ; 21(1): 87, 2021 03 22.
Article in English | MEDLINE | ID: mdl-33752616

ABSTRACT

BACKGROUND: Minqin is suffering from a serious desertification, whereas the knowledge about its bacterial community is limited. Herein, based on Nitraria tangutorum and Haloxylon ammodendron from Minqin, the bacterial community diversities in fixed sandy land, semi-fixed sandy land and shifting sandy land were investigated by combining with culture-dependent and culture-independent methods. RESULTS: Minqin stressed with high salinity and poor nutrition is an oligotrophic environment. Bacterial community in Minqin was shaped primarily by the presence of host plants, whereas the type of plant and sandy land had no marked effect on those, which displayed a better survival in the rhizospheres of N. tangutorum and H. ammodendron. The dominant groups at phyla level were Actinobacteria, Firmicutes, Proteobacteria, Bacteroidetes, Planctomycetes, Chloroflexi, Acidobacteria and Candidate_division_TM7. The abundance of Firmicutes with ability of desiccation-tolerance was significantly higher in harsh environment, whereas Bacteroidetes were mainly distributed in areas with high nutrient content. The abundances of Proteobacteria and Bacteroidetes were relatively high in the rhizospheres of N. tangutorum and H. ammodendron, which had more plant-growth promoting rhizobacteria. A large number of Actinobacteria were detected, of which the most abundant genus was Streptomyces. The physicochemical factors related to the diversity and distribution of the bacterial community were comprehensively analyzed, such as pH, electrical conductivity, soil organic matter, C/N and sand, and the results indicated that Minqin was more suitable for the growth of N. tangutorum, which should be one of most important sand-fixing plants in Minqin. CONCLUSIONS: The bacterial community diversities in different types of sandy lands of Minqin were comprehensively and systematically investigated by culture-dependent and culture-independent approaches, which has a great significance in maintaining/restoring biological diversity.


Subject(s)
Bacteria/classification , Biodiversity , Sand/microbiology , Soil Microbiology , Bacteriological Techniques , China , Desert Climate , RNA, Ribosomal, 16S/genetics
17.
Arch Microbiol ; 203(4): 1753-1766, 2021 May.
Article in English | MEDLINE | ID: mdl-33474608

ABSTRACT

Coastal sands are important natural recreational facilities that have become hotspots for tourism and economic development. However, these sands harbour diverse microbial assemblages that play a critical role in the balance between public health and ecology. In this study, targeted high-throughput sequencing analysis was used to identify sand-borne bacterial populations at four public beaches in Durban. The effect of heavy metal in shaping the distribution of bacterial metacommunities was determined using canonical correspondence analysis (CCA), while the functional gene profiles were predicted using PICRUSt2 analysis. Sequences matching those of the bacterial phylum Proteobacteria were the most abundant in all samples, followed by those of the phyla Firmicutes, Actinobacteria, Bacteroidetes, and Gemmatimonadetes. Genus-level taxonomic analysis showed the presence of 1163 bacterial genera in all samples combined. The distribution of bacterial communities was shaped by heavy metal concentrations, with the distribution of Flavobacteria, Bacteroidia, and Deltaproteobacteria influenced by Pb and Zn, while B and Cr influenced the distribution of Clostridia and Gammaproteobacteria, respectively. Identified antibiotic resistance genes included the peptidoglycan biosynthesis gene II, III, IV, and V, as well as the polymyxin resistance gene, while the virulence genes included the sitA, fimB, aerobactin synthase, and pilL gene. Our findings demonstrate that beach sand-borne bacteria are reservoirs of virulence and antibiotic resistance genes. Contamination of beach sands with heavy metals selects for both heavy metal resistance and antibiotic resistance in beach sand bacterial communities. Children and immunocompromised people engaging in recreational activities on beaches may be exposed to higher risk of infection.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/pathogenicity , Drug Resistance, Bacterial/genetics , Metals, Heavy/pharmacology , Sand/microbiology , Bacteria/genetics , Bacterial Infections/microbiology , Bathing Beaches , Child , Environmental Monitoring , High-Throughput Nucleotide Sequencing , Humans , Microbiota/genetics , Soil Microbiology , South Africa , Virulence , Water Microbiology
18.
Pak J Biol Sci ; 24(12): 1236-1245, 2021 Jan.
Article in English | MEDLINE | ID: mdl-34989201

ABSTRACT

<b>Background and Objective:</b> Biological fertilization in the development of agriculture became one new strategy in the increased production of field crops to decrease the costs of production input and environmental pollution. This study focused on the influence of biochar fertilization on the productivity of faba bean varieties under sandy soils. <b>Materials and Methods:</b> Appreciation of the yield and its components, in addition to measurement of grain protein content as well as carbohydrates (%) of faba bean. <b>Results:</b> The data obtained indicated that the biochar amendment affects plant production at different rates, where the best yield obtained is 90 kg fed<sup>1</sup>. The grain yield increase is significant for the variety's types where, Mariout-2, followed by Nubaria-3 followed by Giza-716 for the addition of 90 kg fed<sup>1</sup> of biochar as referenced by the non-conditioning treatment. Likewise, the protein content was highest in the Mariout-2 variety, followed by Nubaria-3 variety and Giza-716 variety for the addition. This improvement may be regarded to the impact of biochar on the physic-chemical characteristics for the soils, in addition to the biological characteristics. Furthermore, the biochar itself add nutrient to the soil after decomposition. The best improvement happens by the long-term cropping for a long period could be reached up to years. <b>Conclusion:</b> The conclusion that plant growth was better at a high rate (90 kg fed<sup>1</sup>) but the economy of this rate may be questioned, under the condition of the study. However, the validation for different soils may vary with different rates, which needs more research. Also, it is recommended to use Mariout-2 cultivars for their high production under these conditions.


Subject(s)
Charcoal/pharmacology , Oryza/metabolism , Soil/standards , Vicia faba/metabolism , Charcoal/administration & dosage , Oryza/growth & development , Sand/microbiology
19.
J Appl Microbiol ; 130(4): 1232-1244, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33025710

ABSTRACT

AIMS: Microbial induced calcium carbonate precipitation (MICP) is one of the bio-cementation methods for improving granular soils. This study evaluate the feasibility of obtaining a bacterial solution with high optical density and urease activity by an inexpensive corn steep liquor (CSL) medium in non-sterile conditions in order to achieve sand improvement. METHODS AND RESULTS: Corn steep liquor media with different concentrations (different dilution rates) were prepared and, without any autoclaving (non-sterile conditions), different percentage of the inoculum solutions were added to them and incubated. Effect of inoculum solution percentage and CSL dilution rates on specifications of bacterial solution was evaluated. Urease activity and scanning electron microscope (SEM) and X-Ray Diffraction (XRD) were used to efficiency of CLS media in sand improvement. The considerable urease activity was measured as 5·7 mS cm-1  min-1 using nonsterile CLS. By using CYNU (CSL-Yeast extract-NH4Cl-Urea) bacterial solution, the urease activity of 5·5 mS cm-1  min-1 for the OD600 (optical density at 600 nm) of 1·88 and, consequently, specific urease activity of 2·93 mS cm-1  min-1  OD600 -1 was obtained. The highest unconfined compressive strength (811 kPa) was obtained for the CYNU. XRD revealed new calcite peaks next to the quartz peaks. CONCLUSIONS: Production of inexpensive bacterial solution using diluted CSL as the inexpensive, effective and powerful culture media for Sporosarcina pasteurii cultivation in nonsterile conditions, allows geotechnical and biotechnological engineers to use MICP technology more widely in land improvement and field-scale bio-cementation and bioremediation projects. SIGNIFICANCE AND IMPACT OF THE STUDY: Obtaining high urease activity of inexpensive microbial solution using diluted CSL as the culture medium in nonsterile conditions, as the unique results of this study, can be significant in the field of bioremediation studies using MICP.


Subject(s)
Sand/chemistry , Sporosarcina/growth & development , Zea mays/chemistry , Biodegradation, Environmental , Biomineralization , Calcium Carbonate/analysis , Calcium Carbonate/metabolism , Compressive Strength , Cost-Benefit Analysis , Culture Media/chemistry , Sand/microbiology , Sporosarcina/metabolism , Urease/metabolism
20.
Article in English | MEDLINE | ID: mdl-33270002

ABSTRACT

A bacterial strain, designated Y40T, was isolated from sandy soil sampled on the Qinghai-Tibet Plateau. A polyphasic study confirmed the affiliation of the strain with the genus Mesobacillus. Strain Y40T was found to be an aerobic, Gram-stain-positive, motile and rod-shaped bacterium. The strain grew at 10-42 °C, pH 6-9 and with 0-2 % (w/v) NaCl. The diagnostic amino acid was meso-diaminopimeilic acid. MK7 was predominant menaquinone, and iso-C15:0, iso-C17:1 ω10c and anteiso-C15:0 were the major fatty acids. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid. The DNA G+C content was 40.6 mol%. Based on he results of 16S rRNA gene sequence analysis, strain Y40T was phylogenetically closely related to Mesobacillus zeae JJ-247T and Mesobacillus foraminis CV53T, with similarities of 98.0 and 97.7 %, respectively. The average nucleotide identity (ANIb) values between strain Y40T and Mesobacillus zeae JJ-247T and Mesobacillus foraminis CV53T were 69.9 and 70.0 %, respectively. Based on the morphological, physiological, and chemotaxonomic data, it is proposed that strain Y40T (=CICC 24459T=JCM 32794T) should be classified into the genus Mesobacillus as Mesobacillus harenae sp. nov.


Subject(s)
Bacillaceae/classification , Desert Climate , Phylogeny , Sand/microbiology , Soil Microbiology , Bacillaceae/isolation & purification , Bacterial Typing Techniques , Base Composition , Cold Temperature , DNA, Bacterial/genetics , Fatty Acids/chemistry , Nucleic Acid Hybridization , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Tibet , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...