RESUMEN
BACKGROUND: The production of mycelium from endophytic fungi is of interest for applications ranging from inoculants and biofertilizers for crop production to fermentations for enzyme and metabolite production. The purpose of this study was to test the capacity of a solid growth medium based on beet pulp for growing different strains of endophytes. RESULTS: The ergosterol content of inoculated medium was measured to estimate fungal growth. Several parameters related to the preparation of the growth medium, such as water content, calcium salts and incubation time, were evaluated. The greatest fungal biomass production was observed in a medium prepared with a 1:2 (beet pulp:water) ratio, containing calcium sulfate and carbonate. Strains belonging to different fungal species grew well in the growth medium finally selected, producing yields ranging from 50 to 500 g mycelium per kilogram of dry culture, after 22-27 days. Cultures containing up to 400 g beet pulp grew successfully, and could be scaled up. CONCLUSION: A solid culture medium based on beet pulp supported the growth of diverse taxa of fungal endophytes. Both the water and calcium salt content of the growth medium affected the efficiency of mycelium production. Considering these factors, beet pulp medium was an excellent endophyte cultivation medium because of the high yield of fungal biomass observed, together with its ease of handling and scaling-up production. © 2019 Society of Chemical Industry.
Asunto(s)
Beta vulgaris/microbiología , Medios de Cultivo/metabolismo , Endófitos/crecimiento & desarrollo , Hongos/crecimiento & desarrollo , Beta vulgaris/química , Biomasa , Medios de Cultivo/química , Endófitos/metabolismo , Fermentación , Hongos/metabolismo , Micelio/crecimiento & desarrollo , Micelio/metabolismoRESUMEN
We analysed, using a polyphasic taxonomic approach, two bacterial strains coded BSTT30T and BSTT40, isolated in the course of a study of endophytic bacteria occurring in the stems and roots of potatoes growing in soil from Salamanca, Spain. The 16S rRNA gene sequence was identical in both strains and had 98.4 % identity with respect to the closest relatives Erwinia tasmaniensis Et1/99T and Erwinia rhapontici ATCC29283T. Erwinia billingiae E63T and Erwinia toletana A37T were also closely related with 98.2 % sequence similarities, so the novel strains were classified within the genus Erwinia. The analysis of the housekeeping genes gpd, gyrB and rpoD confirmed the phylogenetic affiliation of strains BSTT30T and BSTT40 with similarities of lower than 90 % in all cases with respect to the closest relatives mentioned above. The respiratory quinone of strain BSTT30T was Q8. The major fatty acids were C16 : 0, C16 : 1ω7c/16 : 1ω6c in summed feature 3 and C18 : 1ω7c/18 : 2ω6,9c in summed feature 8. The novel strains were oxidase-negative and catalase-positive. Glucose was fermented without gas production. They were negative for arginine dihydrolase, urease and indole production. The strains could grow at 35 °C and at pH 10. DNA G+C content was 50.1âmol%. DNA-DNA hybridization results showed values of lower than 29 % relatedness with respect to the type strains of the four most closely related species. Therefore, the combined genotypic, phenotypic and chemotaxonomic data support the classification of strains BSTT30T and BSTT40 into a novel species of the genus Erwinia, for which the name Erwinia endophytica sp. nov. is proposed. The type strain is BSTT30T ( = LMG 28457T, CECT 8692T).
RESUMEN
A bacterial strain named BSTT44(T) was isolated in the course of a study of endophytic bacteria occurring in stems and roots of potato growing in a soil from Salamanca, Spain. The 16S rRNA gene sequence had 99.7% identity with respect to that of its closest relative, Pseudomonas psychrophila E-3T, and the next most closely related type strains were those of Pseudomonas fragi, with 99.6% similarity, Pseudomonas deceptionensis, with 99.2% similarity, and Pseudomonas lundensis, with 99.0% similarity; these results indicate that BSTT44(T) should be classified within the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation and showed identities lower than 92% in all cases with respect to the above-mentioned closest relatives. Cells of the strain bore one polar-subpolar flagellum. The respiratory quinone was Q-9.The major fatty acids were C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The strain was oxidase-, catalase- and urease-positive and the arginine dihydrolase system was present, but tests for nitrate reduction, ß-galactosidase production and aesculin hydrolysis were negative. It could grow at 35 °C and at pH 5-9.The DNA G+C content was 60.2 mol%. DNA-DNA hybridization results showed less than 48% relatedness with respect to the type strains of the four most closely related species. Therefore, the combined results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain BSTT44 into a novel species of the genus Pseudomonas, for which the name Pseudomonas endophytica sp. nov. is proposed. The type strain is BSTT44(T) ( = LMG 28456(T) = CECT 8691(T)).
Asunto(s)
Filogenia , Pseudomonas/clasificación , Solanum tuberosum/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Tallos de la Planta/microbiología , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , España , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A bacterial strain designated A4STR04(T) was isolated from the inner root tissue of potatoes in Spain. Phylogenetic analysis based on the 16S rRNA gene sequence placed the isolate into the genus Fontibacillus, being most closely related to Fontibacillus panacisegetis KCTC 13564(T) with 99% identity. The isolate was observed to form Gram-positive, motile and sporulating rods. The catalase test was found to be negative and oxidase positive. Nitrate was found to be reduced to nitrite. ß-Galactosidase and caseinase were observed to be produced but the production of gelatinase, urease, arginine dehydrolase, ornithine and lysine decarboxylase was negative. Aesculin hydrolysis was found to be positive and acetoin production was negative. Growth was found to be supported by many carbohydrates and organic acids as carbon source. MK-7 was the only menaquinone detected and the major fatty acid (61.5%) was identified as anteiso-C(15:0), as occurs in the other species of genus Fontibacillus. The strain A4STR04(T) was found to display a complex lipid profile consisting of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, a glycolipid, two phospholipids, a lipid and two aminophospholipids. Mesodiaminopimelic acid was detected in the peptidoglycan. The G+C content was determined to be 50.5 mol% (Tm). Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain A4STR04(T) (=LMG 28458 (T) = CECT 8693(T)) should be classified as representing a novel species of genus Fontibacillus, for which the name Fontibacillus solani sp. nov. is proposed.
Asunto(s)
Bacillales/clasificación , Bacillales/aislamiento & purificación , Raíces de Plantas/microbiología , Solanum tuberosum/microbiología , Bacillales/genética , Bacillales/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Datos de Secuencia Molecular , Filogenia , Raíces de Plantas/genética , ARN Ribosómico 16S/genéticaRESUMEN
A bacterial strain, OHA11(T), was isolated during the course of a study of phosphate-solubilizing bacteria occurring in a forest soil from Salamanca, Spain. The 16S rRNA gene sequence of strain OHA11(T) shared 99.1% similarity with respect to Pseudomonas baetica a390(T), and 98.9% similarity with the type strains of Pseudomonas jessenii, Pseudomonas moorei, Pseudomonas umsongensis, Pseudomonas mohnii and Pseudomonas koreensis. The analysis of housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation to the genus Pseudomonas and showed similarities lower than 95% in almost all cases with respect to the above species. Cells possessed two polar flagella. The respiratory quinone was Q9. The major fatty acids were C16 : 0, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c/iso-C15 : 0 2-OH). The strain was oxidase-, catalase- and urease-positive, positive for arginine dihydrolase but negative for nitrate reduction, ß-galactosidase production and aesculin hydrolysis. It was able to grow at 31 °C and at pH 11. The DNA G+C content was 58.1 mol%. DNA-DNA hybridization results showed values lower than 49% relatedness with respect to the type strains of the seven closest related species. Therefore, the combined genotypic, phenotypic and chemotaxonomic data support the classification of strain OHA11(T) to a novel species of the genus Pseudomonas, for which the name Pseudomonas helmanticensis sp. nov. is proposed. The type strain is OHA11(T) (â= LMG 28168(T)â= CECT 8548(T)).
Asunto(s)
Filogenia , Pseudomonas/clasificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , España , Árboles , Ubiquinona/químicaRESUMEN
A bacterial strain, designated BAPVE7BT, was isolated from root nodules of Phaseolus vulgaris in Spain. Phylogenetic analysis based on its 16S rRNA gene sequence placed the isolate into the genus Fontibacillus with Fontibacillus panacisegetis KCTC 13564T its closest relative with 97.1 % identity. The isolate was observed to be a Gram-positive, motile and sporulating rod. The catalase test was negative and oxidase was weak. The strain was found to reduce nitrate to nitrite and to produce ß-galactosidase but the production of gelatinase, caseinase, urease, arginine dehydrolase, ornithine or lysine decarboxylase was negative. Acetoin production and aesculin hydrolysis were found to be positive. Growth was observed to be supported by many carbohydrates and organic acids as carbon source. MK-7 was identified as the predominant menaquinone and the major fatty acid (43.7 %) as anteiso-C15:0, as occurs in the other species of the genus Fontibacillus. Strain BAPVE7BT displayed a complex lipid profile consisting of diphosphatidylglycerol, phosphatidylglycerol, four glycolipids, four phospholipids, two lipids, two aminolipids and an aminophospholipid. Mesodiaminopimelic acid was detected in the peptidoglycan. The G+C content was determined to be 45.6 mol% (Tm). Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain BAPVE7BT should be considered a new species of genus Fontibacillus, for which the name Fontibacillus phaseoli sp. nov. is proposed (type strain, LMG 27589T, CECT 8333T).
Asunto(s)
Bacillales/aislamiento & purificación , Phaseolus/microbiología , Nódulos de las Raíces de las Plantas/microbiología , Bacillales/clasificación , Bacillales/genética , Bacillales/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana , Composición de Base , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Datos de Secuencia Molecular , FilogeniaRESUMEN
The aim of this study was to assess the ability of three individual blastocyst morphology parameters - expansion and hatching (EH) stage, inner cell mass (ICM) grade and trophectoderm grade - to predict outcome of a cycle with single-blastocyst transfer. The study was a secondary analysis of data prospectively collected in a large multicentre trial. A total of 618 intracytoplasmic sperm injection patients undergoing ovarian stimulation in a gonadotrophin-releasing hormone antagonist cycle with compulsory single-blastocyst transfer on day 5 were included. In the simple logistic regression analysis, all three blastocyst morphology parameters were statistically significantly (P<0.005 for each) associated with positive human chorionic gonadotrophin, clinical and ongoing pregnancy rates and live birth rates, while only the ICM grade was significantly (P=0.033) associated with early pregnancy loss rate. Blastocyst EH stage was the only significant predictor of live birth (P=0.002) in the multiple logistic regression. In conclusion, although all three blastocyst morphology parameters were related to treatment outcome of fresh single-blastocyst cycles, selection of high-quality blastocysts for transfer should consider first the EH stage. Transfer of a blastocyst with ICM grade A may reduce the risk of early pregnancy loss. Choosing the embryo(s) with the best implantation potential is essential for securing each couple the highest chance of achieving pregnancy after assisted reproduction. The selection of embryo(s) for transfer at the blastocyst stage is based on morphology parameters of expansion and hatching stage, inner cell mass grade and trophectoderm grade. The aim of this study was to assess the relative impact of each parameter in predicting the probability of a successful outcome. The study was a secondary analysis of data prospectively collected in a large multicentre trial. A total of 618 patients who underwent single-blastocyst transfer on day 5 were included. Statistical analysis showed that all three blastocyst morphology parameters were significantly associated with positive human chorionic gonadotrophin (ßHCG), clinical and ongoing pregnancy rates and live birth rates. Only the inner cell mass grade was significantly associated with early pregnancy loss between the positive ßHCG test and confirmation of ongoing pregnancy 10-11weeks after transfer. The expansion and hatching stage was the only significant predictor of live birth in the multiple logistic regression analysis. In conclusion, although all three blastocyst morphology parameters were related to treatment outcome of fresh single-blastocyst cycles, selection of high-quality blastocysts for transfer should consider first the expansion and hatching stage. Transfer of a blastocyst with inner cell mass grade A may reduce the risk of early pregnancy loss.
Asunto(s)
Blastocisto/citología , Transferencia de un Solo Embrión , Adulto , Masa Celular Interna del Blastocisto/ultraestructura , Femenino , Humanos , Modelos Logísticos , Estudios Multicéntricos como Asunto , Embarazo , Resultado del Embarazo , Índice de Embarazo , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
We isolated a bacterial strain designated PCAVU11(T) in the course of a study of phosphate-solubilizing bacteria occurring in rhizospheric soil of Vigna unguiculata (L.) Walp. in Guárico state, Venezuela. The 16S rRNA gene sequence had 99.2â% sequence similarity with respect to the most closely related species, Pseudomonas taiwanensis, and 99.1â% with respect to Pseudomonas entomophila, Pseudomonas plecoglossicida and Pseudomonas monteilii, on the basis of which PCAVU11(T) was classified as representing a member of the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed the phylogenetic affiliation and showed sequence similarities lower than 95â% in all cases with respect to the above-mentioned closest relatives. Strain PCAVU11(T) showed two polar flagella. The respiratory quinone was Q9. The major fatty acids were 16â:â0 (25.7â%), 18â:â1ω7c (20.4â%), 17â:â0 cyclo (11.5â%) and 16â:â1ω7c/15â:â0 iso 2-OH in summed feature 3 (10.8â%). The strain was oxidase-, catalase- and urease-positive, the arginine dihydrolase system was present but nitrate reduction, ß-galactosidase production and aesculin hydrolysis were negative. Strain PCAVU11(T) grew at 44 °C and at pH 10. The DNA G+C content was 61.5 mol%. DNA-DNA hybridization results showed values lower than 56â% relatedness with respect to the type strains of the four most closely related species. Therefore, the results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain PCAVU11(T) as representing a novel species of the genus Pseudomonas, which we propose to name Pseudomonas guariconensis sp. nov. The type strain is PCAVU11(T) (â=âLMG 27394(T)â=âCECT 8262(T)).
Asunto(s)
Fabaceae/microbiología , Filogenia , Pseudomonas/clasificación , Rizosfera , Microbiología del Suelo , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Venezuela , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
The impact of gonadotropins used for COS on the rate of embryo aneuploidy in patients without the negative effects of age as a confounding factor, is still a subject of lively debate. We ran a systematic search for studies in MEDLINE, PubMed, Google Scholar and the Cochrane Library. A librarian coordinated the search in December of 2020. We included all original peer-reviewed papers in English, irrespective of study-design. There were no restrictions concerning method of amplification or platform used to analyze the amplified DNA. We used the PICO model to select the study population. We included women/couples submitted to COS for IVF with the intention to genetically analyze her/their embryos through PGT. The primary outcome was the rate of aneuploidy. We used the Newcastle-Ottawa scale (NOS) score to evaluate the quality of the studies included. The search yielded 73 citations, and 14 were eligible for analysis, which included data on 4805 cycles. Media quality NOS score was 8. Although it has been demonstrated that natural cycles are associated with aneuploidy, it does seem that more robust stimulations are indeed associated with a higher proportion of aneuploidy. Nevertheless, a higher response is associated with an increased number of euploid embryos available for transfer, which translates into more embryo-transfer cycles with a prospective higher cumulative live birth rate. Further evidence is needed to ascertain if there is a negative impact of COS, especially at the cellular level.
Asunto(s)
Pruebas Genéticas , Nacimiento Vivo , Aneuploidia , Femenino , Fertilización In Vitro/métodos , Pruebas Genéticas/métodos , Humanos , Inducción de la Ovulación , Embarazo , Índice de Embarazo , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
Embryo transfer (ET) is the final step of in vitro fertilization (IVF). Different strategies have been proposed to increase the likelihood of implantation, such as post-transfer bed rest. The objective of this manuscript was to compare the clinical outcomes of embryo transfers after IVF of patients offered rest vs. early ambulation. The patient, intervention, comparison, and outcome(s) (PICO) model was used to select the study population, which included women/couples submitted to IVF and prescribed bed rest or early ambulation. Only studies including live birth (LB) as an outcome were included (www.crd.york.ac.uk/PROSPERO/CRD42020188716) A systematic search for studies was conducted on MEDLINE, ClinicalTrials.gov, PubMed, and the Cochrane Library. A librarian coordinated the searches in May 2020, which considered articles published since 1995. All original peer-reviewed articles in English were included, regardless of study design. The search retrieved 27 citations, of which 14 were eligible for full-text analysis and four accepted for inclusion. The studies included data on 21,598 patients/cycles (rest: 20,138; early ambulation: 1,460). Patients prescribed bed rest had an LB rate of 43.6% vs. 52.5% in the individuals not offered bed rest. The meta-analysis yielded an odds ratio of 0.77 (95% CI 0.5-1.2), which means patients on bed rest were 23% less likely to have a LB; nevertheless, this difference was not statistically significant. Considering that there is no difference between the two strategies, there is no evidence to recommend bed rest after embryo transfer.
Asunto(s)
Tasa de Natalidad , Ambulación Precoz , Reposo en Cama , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Nacimiento Vivo , Embarazo , Índice de EmbarazoRESUMEN
Celtica gigantea(= Stipa gigantea) is a large perennial grass which grows in nutrient-poor sandy soils in semiarid zones of the western Iberian Peninsula. The purpose of this work was to find out if culturable fungal symbionts isolated from roots of this wild grass could have growth promoting activity in tritordeum, a hybrid cereal for human consumption. A survey of fungi from the root endosphere of C. gigantea produced an isolate collection consisting of 60 different taxa, mostly ascomycetes. Fungal strains were inoculated into tritordeum plants in order to evaluate their effect in leaf and root biomass, nutrient content, and total antioxidant capacity. Two consecutive screening processes were made to test endophyte effects in plants. In the first screening, 66 strains were inoculated into seedlings by dipping roots in a liquid suspension of inoculum. In the second screening, 13 strains selected from the first screening were inoculated by sowing seeds in a substrate containing inoculum. The inoculation method used in the second screening involved less labor and plant manipulation and improved the quantity and quality of the inoculum, making it more appropriate for big scale experimental inoculation procedures. Several fungal strains promoted leaf or root growth. In particular, a strain belonging to the genus Diaporthe caused an increase in leaf and root biomass in both screening processes, suggesting that this endophyte might have a good potential for field application in tritordeum.