scholarly journals Distribution Dynamics of Vegetative Cells and Cyst of Ceratium hirundinella in Two Reservoirs, Turkey

2017 ◽  
Vol 21 (1) ◽  
pp. 247
Author(s):  
Elif TEZEL ERSANLI ◽  
Seda HASIRCI MUSTAK
Keyword(s):  
Distribution Dynamics ◽  
Vegetative Cells ◽  
Ceratium Hirundinella

Film coating of seeds with Bacillus cereus RS87 spores for early plant growth enhancement

2008 ◽  
Vol 54 (10) ◽  
pp. 861-867 ◽  
Author(s):  
Kanchalee Jetiyanon ◽  
Sakchai Wittaya-Areekul ◽  
Pinyupa Plianbangchang
Keyword(s):  
Plant Growth ◽  
Bacillus Cereus ◽  
Plant Height ◽  
Root Length ◽  
Film Coating ◽  
Field Trials ◽  
Growth Enhancement ◽  
Vegetative Cells ◽  
Plant Growth Promoting ◽  
Growth Promoting

The plant growth-promoting rhizobacterium Bacillus cereus RS87 was previously reported to promote plant growth in various crops in both greenhouse and field trials. To apply as a plant growth promoting agent with practical use, it is essential to ease the burden of routine preparation of a fresh suspension of strain RS87 in laboratory. The objectives of this study were to investigate the feasibility of film-coating seeds with B. cereus RS87 spores for early plant growth enhancement and to reveal the indoleacetic acid (IAA) production released from strain RS87. The experiment consisted of the following 5 treatments: nontreated seeds, water-soaked seeds, film-coated seeds, seeds soaked with vegetative cells of strain RS87, and film-coated seeds with strain RS87 spores. Three experiments were conducted separately to assess seed emergence, root length, and plant height. Results showed that both vegetative cells and spores of strain RS87 significantly promoted (P ≤ 0.05) seed emergence, root length and plant height over the control treatments. The strain RS87 also produced IAA. In conclusion, the film coating of seeds with spores of B. cereus RS87 demonstrated early plant growth enhancement as well as seeds using their vegetative cells. IAA released from strain RS87 would be one of the mechanisms for plant growth enhancement.

scholarly journals ISOLATION OF SPO12–1 AND SPO13–1 FROM A NATURAL VARIANT OF YEAST THAT UNDERGOES A SINGLE MEIOTIC DIVISION

Genetics ◽  
1980 ◽  
Vol 96 (3) ◽  
pp. 567-588 ◽  
Author(s):  
Sue Klapholz ◽  
Rochelle Easton Esposito
Keyword(s):  
Genetic Analysis ◽  
Meiotic Division ◽  
Parental Strain ◽  
Nuclear Division ◽  
Nuclear Genes ◽  
Vegetative Cells ◽  
Total Level ◽  
Natural Variant ◽  
Chromosome Viii

ABSTRACT ATCC4117 is a strain of S. cerevisiae that undergoes a single nuclear division during sporulation to produce asci containing two diploid ascospores (Grewal and Miller 1972). All clones derived from these spores are sporulation-capable and, like the parental strain, form two-spored asci. In this paper, we describe the genetic analysis of ATCC4117. In tetraploid hybrids of vegetative cells of the ATCC4117 diploid and a/a or α/α diploids, the production of two-spored asci is recessive. From these tetraploids, we have isolated two recessive alleles, designated spo12–1 and spo13–1, each of which alone results in the production of asci with two diploid or near-diploid spores. These alleles are unlinked and segregate as single nuclear genes. spo12–1 is approximately 22 cM from its centromere; spo13–1 has been localized to within 1 cM of arg4 on chromosome VIII. This analysis also revealed that ATCC4117 carries a diploidization gene allelic to or closely linked to HO, modifiers that reduce the number of haploid spores per ascus and alleles affecting the total level of sporulation.

Inactivation kinetics of Bacillus cereus vegetative cells and spores from different sources by antimicrobial photodynamic treatment (aPDT)

LWT ◽  
2021 ◽  
Vol 142 ◽  
pp. 111037
Author(s):  
Leonardo do Prado-Silva ◽  
Verônica O. Alvarenga ◽  
Gilberto Ú.L. Braga ◽  
Anderson S. Sant’Ana
Keyword(s):  
Bacillus Cereus ◽  
Inactivation Kinetics ◽  
Photodynamic Treatment ◽  
Vegetative Cells ◽  
Kinetics Of ◽  
Different Sources

New insights on Laminaria digitata ultrastructure through combined conventional chemical fixation and cryofixation

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christos Katsaros ◽  
Sophie Le Panse ◽  
Gillian Milne ◽  
Carl J. Carrano ◽  
Frithjof Christian Küpper
Keyword(s):  
Cell Wall ◽  
General Structure ◽  
Raw Material ◽  
Rocky Shores ◽  
Chemical Fixation ◽  
Laminaria Digitata ◽  
Vegetative Cells ◽  
Biological Studies ◽  
New Findings ◽  
Wide Range

Abstract The objective of the present study is to examine the fine structure of vegetative cells of Laminaria digitata using both chemical fixation and cryofixation. Laminaria digitata was chosen due to its importance as a model organism in a wide range of biological studies, as a keystone species on rocky shores of the North Atlantic, its use of iodide as a unique inorganic antioxidant, and its significance as a raw material for the production of alginate. Details of the fine structural features of vegetative cells are described, with particular emphasis on the differences between the two methods used, i.e. conventional chemical fixation and freeze-fixation. The general structure of the cells was similar to that already described, with minor differences between the different cell types. An intense activity of the Golgi system was found associated with the thick external cell wall, with large dictyosomes from which numerous vesicles and cisternae are released. An interesting type of cisternae was found in the cryofixed material, which was not visible with the chemical fixation. These are elongated structures, in sections appearing tubule-like, close to the external cell wall or to young internal walls. An increased number of these structures was observed near the plasmodesmata of the pit fields. They are similar to the “flat cisternae” found associated with the forming cytokinetic diaphragm of brown algae. Their possible role is discussed. The new findings of this work underline the importance of such combined studies which reveal new data not known until now using the old conventional methods. The main conclusion of the present study is that cryofixation is the method of choice for studying Laminaria cytology by transmission electron microscopy.

scholarly journals Probing the Energetic Metabolism of Resting Cysts under Different Conditions from Molecular and Physiological Perspectives in the Harmful Algal Blooms-Forming Dinoflagellate Scrippsiella trochoidea

2021 ◽  
Vol 22 (14) ◽  
pp. 7325
Author(s):  
Fengting Li ◽  
Aoao Yang ◽  
Zhangxi Hu ◽  
Siheng Lin ◽  
Yunyan Deng ◽  
...  
Keyword(s):  
Low Temperature ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Atp Content ◽  
Energetic Metabolism ◽  
Scrippsiella Trochoidea ◽  
Vegetative Cells ◽  
F1 Atpase ◽  
Atpase Gene ◽  
Resting Cysts

Energetic metabolism is essential in maintaining the viability of all organisms. Resting cysts play important roles in the ecology of dinoflagellates, particularly for harmful algal blooms (HABs)-causative species. However, the energetic metabolism underlying the germination potency maintenance of resting cysts of dinoflagellate have been extremely scarce in studies from physiological and, particularly, molecular perspectives. Therefore, we used the cosmopolitan Scrippsiella trochoidea as a representative of HABs-forming and cyst-producing dinoflagellates in this work to obtain novel insights into the molecular mechanisms, regulating the energetic metabolism in dinoflagellate resting cysts, under different physical condition. As the starting step, we established a cDNA subtractive library via suppression subtractive hybridization (SSH) technology, from which we screened an incomplete sequence for the β subunit of ATP synthase gene (β-F1-ATPase), a key indicator for the status of cell’s energetic metabolism. The full-length cDNA of β-F1-ATPase gene from S.trochoidea (Stβ-F1-ATPase) was then obtained via rapid amplification of cDNA ends (RACE) (Accession: MZ343333). Our real-time qPCR detections, in vegetative cells and resting cysts treated with different physical conditions, revealed that (1) the expression of Stβ-F1-ATPase in resting cysts was generally much lower than that in vegetative cells, and (2) the Stβ-F1-ATPase expressions in the resting cysts under darkness, lowered temperature, and anoxia, and during an extended duration of dormancy, were significantly lower than that in cysts under the condition normally used for culture-maintaining (a 12 h light:12 h dark cycle, 21 °C, aerobic, and newly harvested). Our detections of the viability (via Neutral Red staining) and cellular ATP content of resting cysts, at the conditions corresponding to the abovementioned treatments, showed that both the viability and ATP content decreased rapidly within 12 h and then maintained at low levels within the 4-day experimentation under all the three conditions applied (4 °C, darkness, and anoxia), which are well in accordance with the measurements of the transcription of Stβ-F1-ATPase. These results demonstrated that the energy consumption of resting cysts reaches a low, but somehow stable, level within a short time period and is lower at low temperature, darkness, and anoxia than that at ambient temperature. Our work provides an important basis for explaining that resting cysts survive long-term darkness and low temperature in marine sediments from molecular and physiological levels.

scholarly journals A Role for MMS4 in the Processing of Recombination Intermediates During Meiosis in Saccharomyces cerevisiae

Genetics ◽  
2001 ◽  
Vol 159 (4) ◽  
pp. 1511-1525 ◽  
Author(s):  
Teresa de los Santos ◽  
Josef Loidl ◽  
Brittany Larkin ◽  
Nancy M Hollingsworth
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Meiotic Recombination ◽  
Biochemical Data ◽  
Dna Metabolism ◽  
Spore Viability ◽  
Vegetative Cells ◽  
Recombination Checkpoint

Abstract The MMS4 gene of Saccharomyces cerevisiae was originally identified due to its sensitivity to MMS in vegetative cells. Subsequent studies have confirmed a role for MMS4 in DNA metabolism of vegetative cells. In addition, mms4 diploids were observed to sporulate poorly. This work demonstrates that the mms4 sporulation defect is due to triggering of the meiotic recombination checkpoint. Genetic, physical, and cytological analyses suggest that MMS4 functions after the single end invasion step of meiotic recombination. In spo13 diploids, red1, but not mek1, is epistatic to mms4 for sporulation and spore viability, suggesting that MMS4 may be required only when homologs are capable of undergoing synapsis. MMS4 and MUS81 are in the same epistasis group for spore viability, consistent with biochemical data that show that the two proteins function in a complex. In contrast, MMS4 functions independently of MSH5 in the production of viable spores. We propose that MMS4 is required for the processing of specific recombination intermediates during meiosis.

Sign in / Sign up

Export Citation Format

Share Document