scholarly journals Host Specificity of Sporisorium reilianum Is Tightly Linked to Generation of the Phytoalexin Luteolinidin by Sorghum bicolor

2012 ◽  
Vol 25 (9) ◽  
pp. 1230-1237 ◽  
Author(s):  
Katja Zuther ◽  
Jörg Kahnt ◽  
Jan Utermark ◽  
Julia Imkampe ◽  
Simon Uhse ◽  
...  

The smut fungus Sporisorium reilianum occurs in two varieties (S. reilianum f. sp. reilianum and S. reilianum f. sp. zeae) that cause head smut disease on sorghum and maize, respectively. Prior to plant infection, compatible haploid sporidia of S. reilianum fuse to form infectious dikaryotic hyphae that penetrate the leaf surface, spread throughout the plant, and reach the inflorescences, in which spore formation occurs. To elucidate the basis of host specificity of the two S. reilianum varieties, we compared disease etiology of S. reilianum f. sp. reilianum and S. reilianum f. sp. zeae on sorghum and maize. Both varieties could penetrate and multiply in both hosts. However, red spots appeared on inoculated leaves after sorghum infection with S. reilianum f. sp. zeae. Using matrix-assisted laser desorption-ionization time of flight analysis of leaf extracts, we show that sorghum reacts with the production of the red and orange phytoalexins luteolinidin and apigeninidin upon colonization by S. reilianum f. sp. zeae but not by S. reilianum f. sp. reilianum. Using in vitro growth assays, we demonstrate that luteolinidin but not apigeninidin slows vegetative growth of both S. reilianum f. sp. zeae and S. reilianum f. sp. reilianum. However, the phytoalexin biosynthesis gene SbDFR3 is only induced in sorghum after infection with S. reilianum f. sp. zeae, as shown by quantitative real-time polymerase chain reaction. This suggests that regulation of luteolinidin biosynthesis determines infection success of S. reilianum on sorghum.

1992 ◽  
Vol 67 (01) ◽  
pp. 063-065 ◽  
Author(s):  
Sherryl A M Taylor ◽  
Jacalyn Duffin ◽  
Cherie Cameron ◽  
Jerome Teitel ◽  
Bernadette Garvey ◽  
...  

SummaryChristmas disease was first reported as a distinct clinical entity in two manuscripts published in 1952 (1, 2). The eponym associated with this disorder, is the surname of the first patient examined in detail and reported by Biggs and colleagues in a paper describing the clinical and laboratory features of seven affected individuals (3). This patient has severe factor IX coagulant deficiency (less than 0.01 units/ml) and no detectable circulating factor IX antigen (less than 0.01 units/ml). Coding sequence and splice junctions of the factor IX gene from this patient have been amplified in vitro through the polymerase chain reaction (PCR). One nucleotide substitution was identified at nucleotide 30,070 where a guanine was replaced by a cytosine. This mutation alters the amino acid encoded at position 206 in the factor IX protein from cysteine to serine. The non conservative nature of this substitution, the absence of this change in more than 200 previously sequenced factor IX genes and the fact that the remainder of the coding region of this gene was normal, all provide strong circumstantial evidence in favour of this change being the causative mutation in this patient. The molecular characterization of this novel mutation in the index case of Christmas disease, contributes to the rapidly expanding body of knowledge pertaining to Christmas disease pathogenesis.


Author(s):  
Liliya Vakrilova ◽  
Stanislava Hitrova-Nikolova ◽  
Irena Bradinova

AbstractTriploidy is a rare chromosomal aberration characterized by a karyotype with 69 chromosomes. Triploid fetuses usually are miscarried in early pregnancy. We present a case of a triploid twin and a genetically unaffected co-twin, conceived through in vitro fertilization. A discordant growth was registered at 20 weeks of gestation. Cesarean section was performed at 355/7 gestational week. The second twin was extremely growth restricted female (780 g) with oligohydramnios and severe respiratory distress, and died at 20 hours of age. The autopsy revealed unilobar left lung, bilobar right lung, and cysts of the terminal bronchioles. Quantitative fluorescent polymerase chain reaction detected triploidy compatible pattern. So, early intrauterine growth restriction may be a sign of triploidy, which must be proven by pre or postnatal genetic testing.


Author(s):  
Michael Russelle Alvarez ◽  
Paolo Robert Bueno ◽  
Raymond Oliver Cruz ◽  
Richard Macapulay ◽  
Francis Jayson Vallesfin ◽  
...  

Plant-derived digestive enzyme inhibitors particularly those targeted to carbohydrate metabolism has been the focus of recent studies as natural supplements for weight control and diabetes. The present study explores the salivary amylase inhibition activity of Garcinia mangostana (Linn.) pericarp extracts and Carica papaya (Linn.) leaf extracts and fractions, as well as perform phytochemical screening and quantification, and thin layer – and high performance liquid chromatographic profiling. ­Results show that crude extracts and purified fractions were able to inhibit salivary amylase, with C. papaya fraction 1 being the most active at 30.89% inhibition. Phytochemical screening of all extracts tested ­positive for tannins, glycosides, phenolics, flavonoids and alkaloids. Quantification of phenolics showed that extracts contained high levels of phenolics, with C. papaya crude extract having the highest content with 219.0±12.7 mg GAE/g extract followed by G. mangostana crude extract with 247.1±18.0 mg GAE/g extract. Quantification of total flavonoids also showed C. papaya crude extract to contain the highest content with 55.12±0.679 mg QE/g extract. All extracts contained negligible alkaloid content, though. HPLC and TLC profiling showed several peaks and bands, when viewed in 210 nm and UV light, respectively. These results demonstrate in vitro the salivary amylase inhibitory activity of both plants and their potential as antidiabetic drug candidates; however, further studies need to be done, like isolation and structure elucidation of active components and toxicity assays. Keywords: Amylase inhibition, phytochemical quantification, Carica papaya, Garcinia mangostana


Author(s):  
Shubhaisi Das ◽  
Sunanda Burman ◽  
Goutam Chandra

Background: The only remedy for up surging problem of antibiotic resistance is the discovery of antibacterial agents of natural origin. Objective: The present study was aimed at finding antibacterial potential of crude and solvent extracts of mature leaves of Plumeria pudica. Methods: Antibacterial activity of three different solvent extracts were evaluated in four human and four fish pathogenic bacteria by measuring the zone of inhibition and determining Minimum Inhibitory Concentration and Minimum Bactericidal Concentration values. Standard antibiotics were used as positive control. Preliminary phytochemical screening of most effective extract i.e., ethyl acetate extract, Fourier Transform Infra Red analysis and GC-MS analysis of the Thin Layer Chromatographic (TLC) fraction of ethyl acetate extract were done meticulously. All experiments were done thrice and analyzed statistically. Results: Crude leaf extracts and solvent extracts caused good inhibition of bacterial growth in all selected bacteria. Ethyl acetate extract showed highest inhibition zones in all tested strains with maximum inhibition (19.50±0.29 mm) in Escherichia coli (MTCC 739). MBC/MIC of the extracts indicated that all three solvent extracts were bactericidal. Preliminary phytochemical tests revealed the presence of tannins, steroids and alkaloids and FT-IR analysis revealed presence of many functional groups namely alcoholic, amide, amine salt and aldehyde groups. From the GC-MS analysis of TLC fraction of ethyl acetate extract five different bioactive compounds e.g., 2,4-ditert –butylphenyl 5-hydroxypentanoate, Oxalic acid; allyl nonyl ester, 7,9-Ditert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, Dibutyl phthalate and 2,3,5,8-tetramethyl-decane were identified. Conclusion: Leaf extracts of P. pudica contain bioactive compounds that can be used as broad spectrum bactericidal agent.


2014 ◽  
Vol 81 (1) ◽  
pp. 432-440 ◽  
Author(s):  
T. Sotelo ◽  
M. Lema ◽  
P. Soengas ◽  
M. E. Cartea ◽  
P. Velasco

ABSTRACTGlucosinolates (GSLs) are secondary metabolites found inBrassicavegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about theirin vitrobiocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enrichedBrassicacrops on suppressingin vitrogrowth of two bacterial (Xanthomonas campestrispv. campestris andPseudomonas syringaepv. maculicola) and two fungal (AlternariabrassicaeandSclerotiniascletoriorum)Brassicapathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of differentBrassicaspecies, have potential to inhibit pathogen growth and offer new opportunities to study the use ofBrassicacrops in biofumigation for the control of multiple diseases.


2021 ◽  
Vol 8 (3) ◽  
Author(s):  
Anna Bläckberg ◽  
Linn Falk ◽  
Karl Oldberg ◽  
Lars Olaison ◽  
Magnus Rasmussen

Abstract Background Corynebacterium species are often dismissed as contaminants in blood cultures, but they can also cause infective endocarditis (IE), which is a severe condition. Antibiotic resistance of corynebacteria is increasing making treatment challenging. Reports on IE caused by Corynebacterium species are scarce and more knowledge is needed. Methods Cases of IE caused by Corynebacterium species were identified through the Swedish Registry of Infective Endocarditis. Isolates were collected for species redetermination by matrix-assisted laser desorption ionization-time of flight and for antibiotic susceptibility testing using Etests. Results Thirty episodes of IE due to Corynebacterium species were identified between 2008 and 2017. The median age of patients was 71 years (interquartile range, 60–76) and 77% were male. Corynebacterium striatum (n = 11) was the most common IE causing pathogen followed by Corynebacterium jeikeium (n = 5). Surgery was performed in 50% and in-hospital mortality rate was 13%. Patients with IE caused by Corynebacterium species were significantly more likely to have prosthetic valve endocarditis (70%), compared with patients with IE due to Staphylococcus aureus or non-beta-hemolytic streptococci (14% and 26%, respectively) (P < .0001). Vancomycin was active towards all Corynebacterium isolates, whereas resistance towards penicillin G was common. Conclusions Corynebacterium species cause IE, where prosthetic valves are mainly affected and surgery is often performed. Corynebacterium striatum is an important causative agent of IE within the genus. Antibiotic resistance of corynebacteria is relatively common but resistance towards vancomycin could not be detected in vitro.


2021 ◽  
Vol 82 (1) ◽  
Author(s):  
Anirban Mandal ◽  
Ajeet Kumar Jha ◽  
Dew Biswas ◽  
Shyamal Kanti Guha

Abstract Background The study was conducted to assess the characterization, differentiation, and in vitro cell regeneration potential of canine mesenteric white adipose tissue-derived mesenchymal stem cells (AD-MSCs). The tissue was harvested through surgical incision and digested with collagenase to obtain a stromal vascular fraction. Mesenchymal stem cells isolated from the stromal vascular fraction were characterized through flow cytometry and reverse transcription-polymerase chain reaction. Assessment of cell viability, in vitro cell regeneration, and cell senescence were carried out through MTT assay, wound healing assay, and β-galactosidase assay, respectively. To ascertain the trilineage differentiation potential, MSCs were stained with alizarin red for osteocytes, alcian blue for chondrocytes, and oil o red for adipocytes. In addition, differentiated cells were characterized through a reverse transcription-polymerase chain reaction. Results We observed the elongated, spindle-shaped, and fibroblast-like appearance of cells after 72 h of initial culture. Flow cytometry results showed positive expression for CD44, CD90, and negative expression for CD45 surface markers. Population doubling time was found 18–24 h for up to the fourth passage and 30±0.5 h for the fifth passage. A wound-healing assay was used to determine cell migration rate which was found 136.9 ± 4.7 μm/h. We observed long-term in vitro cell proliferation resulted in MSC senescence. Furthermore, we also found that the isolated cells were capable of differentiating into osteogenic, chondrogenic, and adipogenic lineages. Conclusions Mesenteric white adipose tissue was found to be a potential source for isolation, characterization, and differentiation of MSCs. This study might be helpful for resolving the problems regarding the paucity of information concerning the basic biology of stem cells. The large-scale use of AD-MSCs might be a remedial measure in regenerative medicine.


2021 ◽  
pp. 1-16
Author(s):  
Erika-Alejandra Salinas-Peña ◽  
Martha Mendoza-Rodríguez ◽  
Claudia Velázquez-González ◽  
Carlo Eduardo Medina-Solis ◽  
América Patricia Pontigo-Loyola ◽  
...  

BACKGROUND: The Mexican serviceberry, Malacomeles denticulata, have been used as a successful oral therapy by Mexican communities without enough scientific support. OBJECTIVE: To evaluate the M. denticulata extracts with selective antibacterial properties over dental biofilm bacteria. METHODS: Fruit, Leaf, and Stem of M. denticulata extracts were evaluated with micro-broth dilution method using ATCC bacteria. OD600 values had compared against each positive control (T-student-test). Anaerobically viability had confirmed by Colony-Forming-Units. Thin-Layer-Chromatography was used to identify the number of compounds and phytochemicals to identify secondary metabolites of the selected extracts. RESULTS: Streptococcus mutans showed Minimum-Bactericidal-Concentrations_(MBC) at 30 mg/mL to Fruit, Leaf, and Stem extracts. Periodontal-pathogens Aggregatibacter actinomycetemcomitans serotype b_(MBC = 30 mg/mL_p <  0.01); Fusobacterium nucleatum subsp. nucleatum_(MBC = 30 mg/mL_p<0.001); Parvimonas micra_(MBC = 15 mg/mL_NS); Porphyromonas gingivalis_(MBC = 30 mg/mL_NS); and Prevotella intermedia_(MBC = 3.75 mg/mL_NS) presented higher sensitivity to Leaf-Methanol, than the primary colonizers. Phytochemicals showed positive results to anthraquinones, coumarins, flavonoids, saponins, saponins steroids/triterpenoids, steroids/triterpenes, and tannins/phenols. CONCLUSION: We suggest the natural extracts of fruit and leaf of the Mexican serviceberry for the preventive use over the oral cariogenic or periodontal biofilm species, by their selective antibacterial properties against pathogenic species evaluated in-vitro, and due to the presence of antibacterial secondary metabolites identified as flavonoids and saponins of M. denticulata leaf extracts.


2021 ◽  
Vol 8 (01) ◽  
pp. e34-e42
Author(s):  
Leticia Hiromi Ohashi ◽  
Douglas Costa Gontijo ◽  
Maria Fernanda Alves do Nascimento ◽  
Luciano Ferreira Margalho ◽  
Geraldo Célio Brandão ◽  
...  

AbstractThe present study on Palicourea hoffmannseggiana, which was collected at Marapanim, state of Pará, Brazil, comprises the preparation of different stem and leaf extracts and fractions. Ethanol, hydroethanol, and water extracts were prepared by several methods and evaluated for in vitro activity against resistant Plasmodium falciparum (W2 strain), disclosing a low parasite growth inhibition effect (< 50%). Dereplication by UPLC-DAD-ESI−MS of the leaf ethanol extract showed the presence of two known alkaloids, lyalosidic and strictosidinic acids, along with a sinapoyl ester of lyalosidic acid, with m/z 719.33 [M+H]+, which is possibly a new monoterpene indole alkaloid representative. Sequential liquid-liquid acid-base alkaloid separations from the leaf ethanol extract as well as directly from leaf powder afforded fractions of increased parasite growth inhibition, reaching up to 92.5±0.7%. The most bioactive fractions were shown to contain the β-carboline alkaloids harmane and 4-methyl-β-carboline, along with N-methyl-tryptamine and N-acetyl-tryptamine, while monoterpene indole alkaloids were detected in inactive fractions of these processes. The present results demonstrate that these preliminary fractionation methods can lead to significantly active fractions supporting an adequate scale-up to carrying out the isolation of anti-plasmodial compounds.


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