In vitro spore germination and phytoremediation of Hg and Pb using gametophytes of Pityrogramma calomelanos

2020 ◽  
pp. 1-9
Author(s):  
Roshni Pulukkunadu Thekkeveedu ◽  
Smitha Hegde
Keyword(s):  
Spore Germination ◽  
Pityrogramma Calomelanos

Aliphatic acids as spore germination inhibitors of wood-decay fungi in vitro

1985 ◽  
Vol 63 (2) ◽  
pp. 337-339 ◽  
Author(s):  
Elmer L. Schmidt
Keyword(s):  
Spore Germination ◽  
Germ Tube ◽  
White Rot Fungi ◽  
Wood Decay ◽  
White Rot ◽  
Malt Extract ◽  
Decay Fungi ◽  
Aliphatic Acids ◽  
Wood Decay Fungi

Influences of eight saturated aliphatic acids (C5–C10, C12, and C16) on basidiospores of four isolates of wood-decay fungi (Poria tenuis and Trametes hispida, white rot fungi, and two isolates of the brown rot fungus Gloeophyllum trabeum) were observed in vitro. Spore responses after 24 h on malt extract agar containing 10, 102 or 103 ppm of each acid included normal germination, delay of germ tube emergence, vacuolation and degeneration of spore cytoplasm, and prevention of germ tube development without spore destruction. Acids of chain length C5–C10 prevented spore germination and killed spores of all fungi at concentrations of 20–50 ppm in media, whereas other acids tested were less active. Spore germination assay of decay fungi may prove useful as a screening tool to compare potency of wood preservatives.

An aniline-substituted bile salt analog protects both mice and hamsters from multiple Clostridioides difficile strains

2021 ◽  
Author(s):  
Jacqueline R. Phan ◽  
Dung M. Do ◽  
Minh Chau Truong ◽  
Connie Ngo ◽  
Julian H. Phan ◽  
...  
Keyword(s):  
Bile Salt ◽  
Spore Germination ◽  
Dependent Manner ◽  
Germination Inhibitors ◽  
New Methods ◽  
Clostridioides Difficile ◽  
Antibiotic Associated Diarrhea ◽  
Careful Screening ◽  
Strain Dependent

Clostridioides difficile infection (CDI) is the major identifiable cause of antibiotic-associated diarrhea. The emergence of hypervirulent C. difficile strains has led to increases in both hospital- and community-acquired CDI. Furthermore, CDI relapse from hypervirulent strains can reach up to 25%. Thus, standard treatments are rendered less effective, making new methods of prevention and treatment more critical. Previously, the bile salt analog CamSA was shown to inhibit spore germination in vitro and protect mice and hamsters from C. difficile strain 630. Here, we show that CamSA was less active at preventing spore germination of other C. difficile ribotypes, including the hypervirulent strain R20291. Strain-specific in vitro germination activity of CamSA correlated with its ability to prevent CDI in mice. Additional bile salt analogs were screened for in vitro germination inhibition activity against strain R20291, and the most active compounds were tested against other strains. An aniline-substituted bile salt analog, (CaPA), was found to be a better anti-germinant than CamSA against eight different C. difficile strains. In addition, CaPA was capable of reducing, delaying, or preventing murine CDI signs in all strains tested. CaPA-treated mice showed no obvious toxicity and showed minor effects on their gut microbiome. CaPA’s efficacy was further confirmed by its ability to prevent CDI in hamsters infected with strain 630. These data suggest that C. difficile spores respond to germination inhibitors in a strain-dependent manner. However, careful screening can identify anti-germinants with broad CDI prophylaxis activity.

Impact of the biofungicide tetramycin on the development of Fusarium head blight, grain yield and deoxynivalenol accumulation in wheat

2020 ◽  
Vol 13 (2) ◽  
pp. 235-246
Author(s):  
W.Q. Shi ◽  
L.B. Xiang ◽  
D.Z. Yu ◽  
S.J. Gong ◽  
L.J. Yang
Keyword(s):  
Fusarium Head Blight ◽  
Fusarium Graminearum ◽  
Spore Germination ◽  
Field Experiments ◽  
Synergistic Effects ◽  
Field Trials ◽  
Head Blight ◽  
Mycelium Growth ◽  
Key Aspects

Fusarium graminearum causes Fusarium head blight (FHB), a devastating disease that leads to extensive yield and quality loss in wheat and barley production. Integrated pest management (IPM) is required to control this disease and biofungicides, such as tetramycin, could be a novel addition to IPM strategies. The current study investigated in vitro tetramycin toxicity in Fusarium graminearum and evaluated its effectiveness for the control of Fusarium head blight FHB. Tetramycin was shown to affect three key aspects of Fusarium pathogenicity: spore germination, mycelium growth and deoxynivalenol (DON) production. The in vitro results indicated that tetramycin had strong inhibitory activity on the mycelial growth and spore germination. Field trials indicated that tetramycin treatment resulted in a significant reduction in both the FHB disease index and the level of DON accumulation. The reduced DON content in harvested grain was correlated with the amount of Tri5 mRNA determined by qRT-PCR. Synergistic effects between tetramycin and metconazole, in both the in vitro and field experiments were found. Tetramycin could provide an alternative option to control FHB.

scholarly journals Germinant Synergy FacilitatesClostridium difficileSpore Germination under Physiological Conditions

mSphere ◽  
2018 ◽  
Vol 3 (5) ◽  
Author(s):  
Travis J. Kochan ◽  
Michelle S. Shoshiev ◽  
Jessica L. Hastie ◽  
Madeline J. Somers ◽  
Yael M. Plotnick ◽  
...  
Keyword(s):  
Amino Acids ◽  
Clostridium Difficile ◽  
Spore Germination ◽  
Bile Salts ◽  
Gi Tract ◽  
Infectious Diarrhea ◽  
Content Type ◽  
Increased Risk ◽  
Calcium Reabsorption

ABSTRACTClostridium difficileis a Gram-positive obligate anaerobe that forms spores in order to survive for long periods in the unfavorable environment outside a host.C. difficileis the leading cause of nosocomial infectious diarrhea worldwide.C. difficileinfection (CDI) arises after a patient treated with broad-spectrum antibiotics ingests infectious spores. The first step inC. difficilepathogenesis is the metabolic reactivation of dormant spores within the gastrointestinal (GI) tract through a process known as germination. In this work, we aim to elucidate the specific conditions and the location within the GI tract that facilitate this process. Our data suggest thatC. difficilegermination occurs through a two-step biochemical process that is regulated by pH and bile salts, amino acids, and calcium present within the GI tract. Maximal germination occurs at a pH ranging from 6.5 to 8.5 in the terminal small intestine prior to bile salt and calcium reabsorption by the host. Germination can be initiated by lower concentrations of germinants when spores are incubated with a combination of bile salts, calcium, and amino acids, and this synergy is dependent on the availability of calcium. The synergy described here allows germination to proceed in the presence of inhibitory bile salts and at physiological concentrations of germinants, effectively decreasing the concentrations of nutrients required to initiate an essential step of pathogenesis.IMPORTANCEClostridium difficileis an anaerobic spore-forming human pathogen that is the leading cause of nosocomial infectious diarrhea worldwide. Germination of infectious spores is the first step in the development of aC. difficileinfection (CDI) after ingestion and passage through the stomach. This study investigates the specific conditions that facilitateC. difficilespore germination, including the following: location within the gastrointestinal (GI) tract, pH, temperature, and germinant concentration. The germinants that have been identified in culture include combinations of bile salts and amino acids or bile salts and calcium, butin vitro, these function at concentrations that far exceed normal physiological ranges normally found in the mammalian GI tract. In this work, we describe and quantify a previously unreported synergy observed when bile salts, calcium, and amino acids are added together. These germinant cocktails improve germination efficiency by decreasing the required concentrations of germinants to physiologically relevant levels. Combinations of multiple germinant types are also able to overcome the effects of inhibitory bile salts. In addition, we propose that the acidic conditions within the GI tract regulateC. difficilespore germination and could provide a biological explanation for why patients taking proton pump inhibitors are associated with increased risk of developing a CDI.

scholarly journals Impeding Bacillus spore germination in vitro and in milk by soy glycinin during long cold storage

2016 ◽  
Vol 62 (2) ◽  
pp. 52-59 ◽  
Author(s):  
Samir A. Mahgoub ◽  
Ali O. Osman ◽  
Mahmoud Z. Sitohy
Keyword(s):  
Cold Storage ◽  
Spore Germination

scholarly journals In vitro spore germination and early gametophyte development of Cibotium barometz (L.) J. Sm. in different media

2020 ◽  
Vol 21 (11) ◽  
Author(s):  
Yupi ISNAINI ◽  
Titien Ngatinem Praptosuwiryo
Keyword(s):  
Spore Germination ◽  
Culture Media ◽  
Basal Medium ◽  
Modern Medicine ◽  
Ex Situ ◽  
Naphthalene Acetic Acid ◽  
Gametophyte Development ◽  
In The Wild ◽  
Rare And Endangered

Abstract. Isnaini Y, Praptosuwiryo TNg. 2020. In vitro spore germination and early gametophyte development of Cibotium barometz (L.) J. Sm. in different media. Biodiversitas 21: 5373-5381. Cibotium barometz (L.) J. Sm. is known as the golden chicken fern and included in Appendix II of CITES. It is an important export commodity for traditional and modern medicine. Globally, populations of this species are under significant pressure due to overexploitation in the wild. In vitro culture is one of the technologies used for ex-situ propagation and conservation of rare and endangered ferns and lycophytes. This study’s objectives were: (i) to observe in vitro spore germination and early gametophyte development of C. barometz, and (ii) to determine the best culture medium for rapid spore germination and early development of the gametophytes. The sterilized spores were sown in half-strength Murashige & Skoog (½MS) basal medium supplemented with combinations of 6-Benzylaminopurine (BAP) and α-Naphthalene acetic acid (NAA). A factorial combination of four BAP concentrations (0, 2, 4, and 6 mg L-1) with four concentrations of NAA (0; 0.01; 0.03 and 0.05 mg L-1) created 16 treatments replicated in a Completely Randomized Design. Spore germination of C. barometz was observed to be Vittaria-type, and its prothallial development was Drynaria-type. Spore germination started 7-14 days after sowing. Young heart-shape gametophytes consisting of 110-240 cells were formed in 45-61 days after sowing. The two best spore culture media for rapid spore germination and development of C. barometz gametophytes were ½ MS with or without 2 mg L-1 BAP.

Characterization of cDNA clones specific for sequences developmentally regulated during Dictyostelium discoideum spore germination

1983 ◽  
Vol 3 (11) ◽  
pp. 1943-1948
Author(s):  
L J Kelly ◽  
R Kelly ◽  
H L Ennis
Keyword(s):  
Dictyostelium Discoideum ◽  
Spore Germination ◽  
Developmental Regulation ◽  
Blot Hybridization ◽  
Southern Blot Hybridization ◽  
In Vitro Translation ◽  
Cdna Clones ◽  
Molecular Weights ◽  
Multiple Copies

Spore germination in the slime mold Dictyostelium discoideum was used as a model to study the developmental regulation of protein and mRNA synthesis. Changes in the synthesis of these macromolecules occur during the transition from dormant spore to amoebae. The study of the mechanisms which regulate the quantity and quality of protein synthesis can best be accomplished with cloned genes. cDNA clones which hybridized primarily with mRNAs from only spores or germinating spores and not with growing amoebae were collected. Three such clones, denoted pLK109, pLK229, and pRK270, were isolated and had inserts of approximately 500, 1,200, and 690 base pairs, respectively. Southern blot hybridization experiments suggested that each of the genes is present in multiple copies in the D. discoideum genome. RNA blot hybridizations were performed to determine the sizes of the respective mRNAs and their developmental regulation. The mRNA that hybridized to pLK109 DNA was present predominantly in spores and at 1 h after germination but was absent in growing amoebae. Its concentration dramatically dropped at 3 h. The mRNA present in spores is apparently larger (approximately 0.5 kilobase) than in the later stages of germination (0.4 kilobase), indicating processing of the RNA during germination. The mRNA that hybridized to pLK229 DNA was approximately 1.0 kilobase and was present in very low amounts during growth. Its concentration rose until 1 h after spore germination and decreased thereafter. pRK270-specific RNA was approximately 2.7 kilobases and was found predominantly at 1 h after germination. It was present in lower concentrations at 2 and 3 h after germination and was absent in spores and amoebae. In vitro translation of mRNA selected from 1-h polyadenylated RNA which was hybridized to pLK109 or pLK229 DNA gave proteins of molecular weights consistent with the sizes of the mRNAs as determined by the RNA blot analysis.

Screening of Existing and New Boxwood Cultivars for Disease Resistance and In Vitro Fungicide Screening to Manage Boxwood Dieback Caused by Colletotrichum theobromicola

2021 ◽  
Author(s):  
Harleen Kaur ◽  
Monique DeSouza ◽  
Raghuwinder "Raj" Singh
Keyword(s):  
Active Ingredient ◽  
Spore Germination ◽  
Mycelial Growth ◽  
Management Practices ◽  
Management Strategies ◽  
Host Susceptibility ◽  
Germination Inhibition ◽  
Industry Professionals ◽  
The U.S

Boxwood is one of the most common and widely planted perennial ornamentals in both home gardens and commercial landscapes. Recently reported boxwood dieback, a fungal disease caused by Colletotrichum theobromicola, has been spreading at an alarming rate within the U.S. Boxwood breeders, nursery growers, and landscape professionals have shown great concerns regarding the lack of effective management practices. Therefore, the primary objectives of this study were to devise effective disease management strategies including screening cultivars to determine their susceptibility to boxwood dieback and screening various fungicides to determine their effectiveness in managing the disease. Host range studies were conducted by screening a wide variety of boxwood cultivars under greenhouse conditions. Although, boxwood cultivar ‘Little Missy’ showed much delayed symptom expression as compared to rest of the cultivars but none of the 11 cultivars were found to be resistance to boxwood dieback. In vitro screening of nine fungicides was conducted to determine mycelial growth as well as spore germination inhibition of eight isolates of C. theobromicola collected from eight states in the U.S. Of the nine fungicides, difenoconazole+pydiflumetofen showed maximum mycelial growth and spore germination inhibition at 1 ppm active ingredient followed by fluxapyroxad+pyraclostrobin, and pyraclostrobin+boscalid at 5 ppm active ingredient. Azoxystrobin+benzovindiflupyr significantly inhibited mycelial growth at 1 ppm but reduced spore germination at 10 ppm active ingredient. This study provides the boxwood industry professionals with critical and applied information pertaining to host susceptibility and fungicide efficacy to effectively mitigate boxwood dieback and to reduce its further spread.

scholarly journals Hevein-Like Antimicrobial Peptides Wamps: Structure–Function Relationship in Antifungal Activity and Sensitization of Plant Pathogenic Fungi to Tebuconazole by WAMP-2-Derived Peptides

2020 ◽  
Vol 21 (21) ◽  
pp. 7912 ◽  
Author(s):  
Tatyana Odintsova ◽  
Larisa Shcherbakova ◽  
Marina Slezina ◽  
Tatyana Pasechnik ◽  
Bakhyt Kartabaeva ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Antimicrobial Peptides ◽  
Structure Function ◽  
Spore Germination ◽  
Pathogenic Fungi ◽  
Plant Pathogenic Fungi ◽  
Fungal Cell ◽  
Structure Function Relationship ◽  
Function Relationship

Hevein-like antimicrobial peptides (AMPs) comprise a family of plant AMPs with antifungal activity, which harbor a chitin-binding site involved in interactions with chitin of fungal cell walls. However, the mode of action of hevein-like AMPs remains poorly understood. This work reports the structure–function relationship in WAMPs—hevein-like AMPs found in wheat (Triticum kiharae Dorof. et Migush.) and later in other Poaceae species. The effect of WAMP homologues differing at position 34 and the antifungal activity of peptide fragments derived from the central, N- and C-terminal regions of one of the WAMPs, namely WAMP-2, on spore germination of different plant pathogenic fungi were studied. Additionally, the ability of WAMP-2-derived peptides to potentiate the fungicidal effect of tebuconazole, one of the triazole fungicides, towards five cereal-damaging fungi was explored in vitro by co-application of WAMP-2 fragments with Folicur® EC 250 (25% tebuconazole). The antifungal activity of WAMP homologues and WAMP-2-derived peptides varied depending on the fungus, suggesting multiple modes of action for WAMPs against diverse pathogens. Folicur® combined with the WAMP-2 fragments inhibited the spore germination at a much greater level than the fungicide alone, and the type of interactions was either synergistic or additive, depending on the target fungus and concentration combinations of the compounds. The combinations, which resulted in synergism and drastically enhanced the sensitivity to tebuconazole, were revealed for all five fungi by a checkerboard assay. The ability to synergistically interact with a fungicide and exacerbate the sensitivity of plant pathogenic fungi to a commercial antifungal agent is a novel and previously uninvestigated property of hevein-like AMPs.

In vitro culture of arbuscular mycorrhizal fungus and Frankia for inoculation of micropropagated Casuarina equisetifolia L.

1999 ◽  
Vol 77 (9) ◽  
pp. 1391-1397
Author(s):  
Genevieve Louise Mark ◽  
John E Hooker ◽  
Alexander Hahn ◽  
Chris T Wheeler
Keyword(s):  
Spore Germination ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal Fungus ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Dichlorophenoxyacetic Acid ◽  
Casuarina Equisetifolia ◽  
Half Strength ◽  
2,4 Dichlorophenoxyacetic Acid

Micropropagated, rooted, and calli explants of Casuarina equisetifolia L. were inoculated with Frankia UGL 020605S and the arbuscular mycorrhizal fungus (AMF) Glomus mosseae, in single and dual co-culture, in vitro. Different micropropagation media formulations were evaluated for their capacity to stimulate germination of G. mosseae spores and growth of Frankia. Murashige and Skoog basal nutrient (half strength) medium, supplemented with 6-benzylaminopurine (BAP), 2,4-dichlorophenoxyacetic acid (2,4-D), and pyruvate was selected for the in vitro co-culture of C. equisetifolia callus explants, G. mosseae, and Frankia. This medium (M4) supported 70% AMF spore germination with 44 and 34% of the germinating spores producing single and branched hyphal strands, respectively. Hoaglands (quarter strength, modified by Hoaglands and Arnon (1950)) nutrient medium (M5) with no supplements was selected for the in vitro co-culture of rooted C. equisetifolia explants, G. mosseae, and Frankia and supported 57% AMF spore germination with 29 and 40% of the germinating spores producing single and branched hyphal strands, respectively. Both media supported significant growth of Frankia. In both cases agar was substituted with Terragreen(r). AMF appressoria and intercellular hyphae were observed in rooted C. equisetifolia at 28 days; arbuscule formation occurred at 56 days postinoculation. Frankia infection was evident after 28 days. This was observed in both dual and single in vitro co-cultures. No specific immunofluorescent or immunogold reactions to monoclonal antibodies (mABs) anti-Frankia < 8C5 > and anti-G. mosseae < F5G5 > were evident in C. equisetifolia callus explants.Key words: arbuscular mycorrhizal fungi (AMF), Frankia, Casuarina, micropropagation, immunofluorescent labelling.

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