The Mitochondrial Toxin Produced by Streptomyces griseus Strains Isolated from an Indoor Environment Is Valinomycin

1998 ◽  
Vol 64 (12) ◽  
pp. 4767-4773 ◽  
Author(s):  
M. A. Andersson ◽  
R. Mikkola ◽  
R. M. Kroppenstedt ◽  
F. A. Rainey ◽  
J. Peltola ◽  
...  
Keyword(s):  
Indoor Environment ◽  
Membrane Integrity ◽  
Streptomyces Griseus ◽  
Dry Weight ◽  
Sperm Cells ◽  
Fragmentation Pattern ◽  
Day Care Centers ◽  
First Report ◽  
Mitochondrial Toxin ◽  
Boar Semen

ABSTRACT Actinomycete isolates from indoor air and dust in water-damaged schools and children’s day care centers were tested for toxicity by using boar spermatozoa as an indicator. Toxicity was detected in extracts of four strains which caused a loss of sperm motility, and the 50% effective concentrations (EC50) were 10 to 63 ng (dry weight) ml of extended boar semen−1. The four strains were identified as Streptomyces griseus strains by 16S ribosomal DNA and chemotaxonomic methods. The four S. griseus strains had similar effects on sperm cells, including loss of motility and swelling of mitochondria, but we observed no loss of plasma membrane integrity or depletion of cellular ATP. None of the effects was observed with sperm cells exposed to extracts of other indoor actinomycete isolates at concentrations of ≥5,000 to 72,000 ng ml−1. The toxin was purified from all four strains and was identified as a dodecadepsipeptide, and the fragmentation pattern obtained by tandem mass spectrometry was identical to that of valinomycin. Commercial valinomycin had effects in sperm cells that were identical to the effects of the four indoor isolates of S. griseus. The EC50 of purified toxin from the S. griseus strains were 1 to 3 ng ml of extended boar semen−1, and the EC50 of commercial valinomycin was 2 ng ml of extended boar semen−1. To our knowledge, this is the first report of the presence of ionophoric toxin producers in an indoor environment and the first report of valinomycin-producing strains identified as S. griseus.

scholarly journals A Novel Sensitive Bioassay for Detection ofBacillus cereus Emetic Toxin and Related Depsipeptide Ionophores

1998 ◽  
Vol 64 (4) ◽  
pp. 1338-1343 ◽  
Author(s):  
M. A. Andersson ◽  
R. Mikkola ◽  
J. Helin ◽  
M. C. Andersson ◽  
M. Salkinoja-Salonen
Keyword(s):  
Membrane Integrity ◽  
Effective Concentration ◽  
Fragmentation Pattern ◽  
Electrospray Tandem Mass Spectrometry ◽  
Membrane Channel ◽  
Contaminated Food ◽  
Rapid Bioassay ◽  
Boar Semen ◽  
Boar Spermatozoa ◽  
Ofbacillus Cereus

ABSTRACT Of the toxins produced by Bacillus cereus, the emetic toxin is likely the most dangerous but, due to the lack of a suitable assay, the least well known. In this paper, a new, sensitive, inexpensive, and rapid bioassay for detection of the emetic toxin ofB. cereus is described. The assay is based on the loss of motility of boar spermatozoa upon 24 h of exposure to extracts of emetic B. cereus strains or contaminated food. The paralyzed spermatozoa exhibited swollen mitochondria, but no depletion of cellular ATP or damage to plasma membrane integrity was observed. Analysis of the purified toxin by electrospray tandem mass spectrometry showed that it was a dodecadepsipeptide with a mass fragmentation pattern similar to that described for cereulide. The 50% effective concentration of the purified toxin to boar spermatozoa was 0.5 ng of purified toxin ml of extended boar semen−1. This amount corresponds to 104 to 105 CFU of B. cereus cells. No toxicity was detected for 27 other B. cereus strains up to 108 CFU ml−1. The detection limit for food was 3 g of rice containing 106 to 107 CFU of emetic B. cereusper gram. Effects similar to those provoked by emetic B. cereus toxin were also induced in boar spermatozoa by valinomycin and gramicidin at 2 and 3 ng ml of extended boar semen−1, respectively. The symptoms provoked by the toxin in spermatozoa indicated that B. cereus emetic toxin was acting as a membrane channel-forming ionophore, damaging mitochondria and blocking the oxidative phosphorylation required for the motility of boar spermatozoa.

scholarly journals Cooling of equine semen at 16°C for 36 hours with addition of different glutathione concentrations

2015 ◽  
Vol 36 (6) ◽  
pp. 3699
Author(s):  
Rodrigo Arruda de Oliveira ◽  
Marco Antônio De Oliveira Viu ◽  
Maria Lúcia Gambarini
Keyword(s):  
Lipid Peroxidation ◽  
Sperm Motility ◽  
Membrane Integrity ◽  
Membrane Lipid ◽  
Sperm Cells ◽  
Sperm Viability ◽  
Membrane Lipid Peroxidation ◽  
Acrosomal Membrane ◽  
In Vitro Effects

Handling equine semen during the refrigeration process reduces sperm viability, and consequently causes membrane lipid peroxidation, among other challenges. The present study aimed to evaluate the in vitro effects of glutathione (control, 1. 0, 1. 5, and 2. 5 mM) on equine semen in a refrigeration protocol of 16ºC for 36 hours. The following variables were evaluated after 0, 12, 24, and 36 hours refrigeration: total sperm motility, vigor, viability, and plasma and acrosomal membrane integrity. Motility was higher with 2. 5mM of glutathione (57. 8 ± 7. 3) after 12 hours of refrigeration compared to the control (53. 2 ± 8. 3) (P < 0. 05). After 36 hours of refrigeration, motility was higher with 1. 5 mM (43. 4 ± 12. 7) and 2. 5mM glutathione (45. 5 ± 6. 2), than it was with 1mM glutathione (38. 2 ± 9) and the control (35. 5 ± 18. 4) (P < 0. 05), respectively. Vigor was highest with 1. 5mM glutathione (3. 7 ± 0. 3) after 36 hours compared to the control (3. 2 ± 1. 1), (P < 0. 05). Viability differed between control and 1mM treatments (79. 5 ± 1. 8) only after 24 hours (75. 5 ± 9. 7) (P < 0. 05). Throughout the investigation, no significant differences were noted in plasma and acrosomal membrane integrity (P > 0. 05). The 1. 5 and 2. 5mM glutathione levels were more efficient in protecting sperm cells and yielded higher total motility values after 36 hours of refrigeration.

scholarly journals Melatonin Effect on Cryopreserved Sperm Cells of Crioulo Stallions

2020 ◽  
Vol 5 (2) ◽  
pp. 1-8
Author(s):  
Eraldo L Zanella
Keyword(s):  
Plasma Membrane ◽  
Sperm Motility ◽  
Membrane Integrity ◽  
Male Gamete ◽  
The Body ◽  
Cellular Damage ◽  
Ros Generation ◽  
Sperm Cells ◽  
Beneficial Effects ◽  
Endogenous Antioxidant

The freezing/thawing process of spermatozoa can cause cellular damage to the male gamete, decreasing the fertilization potential due to the increase in the production of reactive oxygen species (ROS). Melatonin is a potent endogenous antioxidant that protects the body against the damage caused by ROS. This study has evaluated different melatonin concentrations on the sperm viability of cryopreserved semen of Crioulo stallions. For that, three ejaculates were collected from five stallions diluted in a commercial extender followed by centrifugation and resuspension in a commercial freezing extender supplemented with 0; 1.25; 2.5. 5mM of Melatonin before the cryopreservation process. After thawing, the evaluation was performed assessing motility and flow cytometry evaluations: the plasma membrane integrity (PI), the integrity of the acrosomal membrane (FITC-PNA), mitochondrial membrane potential (JC1), and ROS generation (DCF-DA). Our results showed that sperm motility in the group without Melatonin and the 1.25mM group did not show the difference; however, the groups 2.5mM and 5mM presented a reduction in sperm motility. The 1.25 mM concentration was able to protect the plasma membrane during the cryopreservation process, in addition to showing a significant reduction in the production of ROS and increasing the percentage of sperm with integral acrosome. It can also be seen that high concentrations of Melatonin did not show beneficial effects. In conclusion, the addition of 1.25 mM of the Melatonin in Crioulo sperm cells showed to have a protective effect on the sperm cell during cryopreservation.

scholarly journals Assessment of quality in specific fractions of Large White Yorkshire boar semen

2021 ◽  
Vol 52 (2) ◽  
Author(s):  
K. G. Ambily ◽  
Malati Naik ◽  
Hiron M. Harshan ◽  
C. Jayakumar ◽  
M. P. Unnikrishnan ◽  
...  
Keyword(s):  
Cold Shock ◽  
Sperm Concentration ◽  
Membrane Integrity ◽  
Membrane Cholesterol ◽  
Large White ◽  
Progressive Motility ◽  
Sperm Membrane ◽  
Boar Semen ◽  
Quality Assessments

Boar semen is voluminous and ejaculated as jets or fractions of pre-sperm, sperm rich (SRF) and post-sperm rich fractions. Recent studies have reported more resilient characteristics of sperm in initial portions of SRF towards cold shock and cryopreservation. The present study was conducted to assess the quality of specific fractions of SRF, namely, first 10mL of SRF (F1) and rest of SRF (F2) in Large white Yorkshire (LWY) boar semen. Ejaculates were collected using gloved-hand technique and were subjected to quality assessments of volume, pH, sperm progressive motility, concentration, plasma membrane integrity, abnormality, acrosome integrity and sperm membrane cholesterol. Upon statistical analysis, significant differences were noticed in volume, pH, sperm concentration and sperm membrane cholesterol between fractions of the ejaculate.

scholarly journals First Report of Fusarium proliferatum Causing Root Rot on Soybean (Glycine max) in the United States

Plant Disease ◽  
2011 ◽  
Vol 95 (10) ◽  
pp. 1316-1316 ◽  
Author(s):  
M. M. Díaz Arias ◽  
G. P. Munkvold ◽  
L. F. Leandro
Keyword(s):  
United States ◽  
Root Rot ◽  
Morphological Characteristics ◽  
Dry Weight ◽  
The United States ◽  
Growth Stages ◽  
Species Identity ◽  
First Report ◽  
Soybean Roots ◽  
Soybean Diseases

Fusarium spp. are widespread soilborne pathogens that cause important soybean diseases such as damping-off, root rot, Fusarium wilt, and sudden death syndrome. At least 12 species of Fusarium, including F. proliferatum, have been associated with soybean roots, but their relative aggressiveness as root rot pathogens is not known and pathogenicity has not been established for all reported species (2). In collaboration with 12 Iowa State University extension specialists, soybean roots were arbitrarily sampled from three fields in each of 98 Iowa counties from 2007 to 2009. Ten plants were collected from each field at V2-V3 and R3-R4 growth stages (2). Typical symptoms of Fusarium root rot (2) were observed. Symptomatic and asymptomatic root pieces were superficially sterilized in 0.5% NaOCl for 2 min, rinsed three times in sterile distilled water, and placed onto a Fusarium selective medium. Fusarium colonies were transferred to carnation leaf agar (CLA) and potato dextrose agar and later identified to species based on cultural and morphological characteristics. Of 1,230 Fusarium isolates identified, 50 were recognized as F. proliferatum based on morphological characteristics (3). F. proliferatum isolates produced abundant, aerial, white mycelium and a violet-to-dark purple pigmentation characteristic of Fusarium section Liseola. On CLA, microconidia were abundant, single celled, oval, and in chains on monophialides and polyphialides (3). Species identity was confirmed for two isolates by sequencing of the elongation factor (EF1-α) gene using the ef1 and ef2 primers (1). Identities of the resulting sequences (~680 bp) were confirmed by BLAST analysis and the FUSARIUM-ID database. Analysis resulted in a 99% match for five accessions of F. proliferatum (e.g., FD01389 and FD01858). To complete Koch's postulates, four F. proliferatum isolates were tested for pathogenicity on soybean in a greenhouse. Soybean seeds of cv. AG2306 were planted in cones (150 ml) in autoclaved soil infested with each isolate; Fusarium inoculum was applied by mixing an infested cornmeal/sand mix with soil prior to planting (4). Noninoculated control plants were grown in autoclaved soil amended with a sterile cornmeal/sand mix. Soil temperature was maintained at 18 ± 1°C by placing cones in water baths. The experiment was a completely randomized design with five replicates (single plant in a cone) per isolate and was repeated three times. Root rot severity (visually scored on a percentage scale), shoot dry weight, and root dry weight were assessed at the V3 soybean growth stage. All F. proliferatum isolates tested were pathogenic. Plants inoculated with these isolates were significantly different from the control plants in root rot severity (P = 0.001) and shoot (P = 0.023) and root (P = 0.013) dry weight. Infected plants showed dark brown lesions in the root system as well as decay of the entire taproot. F. proliferatum was reisolated from symptomatic root tissue of infected plants but not from similar tissues of control plants. To our knowledge, this is the first report of F. proliferatum causing root rot on soybean in the United States. References: (1) D. M. Geiser et al. Eur. J. Plant Pathol. 110:473, 2004. (2) G. L. Hartman et al. Compendium of Soybean Diseases. 4th ed. The American Phytopathologic Society, St. Paul, MN, 1999. (3) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Publishing, Oxford, UK, 2006. (4) G. P. Munkvold and J. K. O'Mara. Plant Dis. 86:143, 2002.

scholarly journals Silicon-Mediated Enhancement of Heavy Metal Tolerance in Rice at Different Growth Stages

2018 ◽  
Vol 15 (10) ◽  
pp. 2193 ◽  
Author(s):  
Fei Huang ◽  
Xiao-Hui Wen ◽  
Yi-Xia Cai ◽  
Kun-Zheng Cai
Keyword(s):  
Heavy Metal ◽  
Metal Tolerance ◽  
Heavy Metal Tolerance ◽  
Membrane Integrity ◽  
Dry Weight ◽  
Growth Stages ◽  
Photosynthetic Parameters ◽  
Cell Membrane Integrity ◽  
Zn Toxicity ◽  
Different Growth Stages

Silicon (Si) plays important roles in alleviating heavy metal stress in rice plants. Here we investigated the physiological response of rice at different growth stages under the silicon-induced mitigation of cadmium (Cd) and zinc (Zn) toxicity. Si treatment increased the dry weight of shoots and roots and reduced the Cd and Zn concentrations in roots, stems, leaves and grains. Under the stress of exposure to Cd and Zn, photosynthetic parameters including the chlorophyll content and chlorophyll fluorescence decreased, while the membrane permeability and malondialdehyde (MDA) increased. Catalase (CAT) and peroxidase (POD) activities increased under heavy metals stress, but superoxide dismutase (SOD) activities decreased. The magnitude of these Cd- and Zn-induced changes was mitigated by Si-addition at different growth stages. The available Cd concentration increased in the soil but significantly decreased in the shoots, which suggested that Si treatment prevents Cd accumulation through internal mechanisms by limiting Cd2+ uptake by the roots. Overall, the phenomena of Si-mediated alleviation of Cd and excess Zn toxicity in two rice cultivars could be due to the limitation of metal uptake and transport, resulting in an improvement in cell membrane integrity, photosynthetic performance and anti-oxidative enzyme activities after Si treatment.

scholarly journals Pseudomonas aeruginosa Alginate Benefits Staphylococcus aureus?

2020 ◽  
Vol 202 (8) ◽  
Author(s):  
Michael J. Schurr
Keyword(s):  
Cystic Fibrosis ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Cell Membrane ◽  
Membrane Integrity ◽  
Partial Explanation ◽  
Content Type ◽  
First Report ◽  
Cell Membrane Integrity ◽  
Link Type

ABSTRACT In this issue of Journal of Bacteriology, Price et al. show that the Pseudomonas aeruginosa-produced exopolysaccharide alginate protects Staphylococcus aureus by dampening the expression of P. aeruginosa virulence products that usually inhibit S. aureus respiration and cell membrane integrity when the two organisms compete in other environments (C. E. Price, D. G. Brown, D. H. Limoli, V. V. Phelan, and G. A. O’Toole, J Bacteriol 202:e00559-19, 2020, https://doi.org/10.1128/jb.00559-19). This is the first report that exogenously added alginate affects P. aeruginosa competition and provides a partial explanation for S. aureus and P. aeruginosa coinfections in cystic fibrosis.

scholarly journals Toxic-Metabolite-Producing Bacteria and Fungus in an Indoor Environment

2001 ◽  
Vol 67 (7) ◽  
pp. 3269-3274 ◽  
Author(s):  
J. Peltola ◽  
M. A. Andersson ◽  
T. Haahtela ◽  
H. Mussalo-Rauhamaa ◽  
F. A. Rainey ◽  
...  
Keyword(s):  
Mitochondrial Membrane ◽  
Indoor Environment ◽  
Bacillus Pumilus ◽  
Dry Weight ◽  
Toxic Metabolite ◽  
Toxic Substances ◽  
Bacterial Isolates ◽  
Bacillus Simplex ◽  
Membrane Barrier ◽  
Boar Spermatozoa

ABSTRACT Toxic-metabolite-emitting microbes were isolated from the indoor environment of a building where the occupant was suffering serious building-related ill-health symptoms. Toxic substances soluble in methanol and inhibitory to spermatozoa at <10 μg (dry weight) ml−1 were found from six bacterial isolates and one fungus. The substances from isolates of Bacillus simplexand from isolates belonging to the actinobacterial generaStreptomyces and Nocardiopsis were mitochondriotoxic. These substances dissipated the mitochondrial membrane potential (Δψ) of boar spermatozoa. The substances from the Streptomyces isolates also swelled the mitochondria. The substances from isolates of Trichoderma harzianum Rifai and Bacillus pumilus damaged the cell membrane barrier function of sperm cells.

Recovery of epididymal spermatozoa from bull and red deer, stored at different times and temperatures before freezing - thawing

2012 ◽  
Vol 52 (8) ◽  
pp. 741 ◽  
Author(s):  
V. Malcotti ◽  
V. Pelufo ◽  
N. Bergamo ◽  
E. Aisen
Keyword(s):  
Cervus Elaphus ◽  
Red Deer ◽  
Treatment Time ◽  
Membrane Integrity ◽  
Sperm Chromatin ◽  
Sperm Cells ◽  
Post Mortem ◽  
Epididymal Spermatozoa ◽  
Motility Rate

In order to preserve male germoplasm, the recovery and cryopreservation of spermatozoa from the epididymides of hunted animals represents an accessible source of gametes. As a first experimental model, epididymal spermatozoa from slaughtered bulls were recovered at 30, 54, 78 and 102 h after death. The scrotal contents were stored at either 5 or 20°C. The sperm cells of each treatment (time + temperature combinations) were frozen with Triladyl (T) or Triladyl + Trehalose (TT) diluents. In order to assess sperm viability and integrity, post-thawing evaluation included individual motility, supravital stain, hyperosmotic swelling test (E+), acrosome status and sperm chromatin structure assay. Both at raw and post-refrigerated states, the sperm motility rate was higher in sperm obtained from epidydmes stored at 5°C, compared with those stored at 20°C for all collection times. Sperm collected at 102 h after death from epididymides stored at 5°C maintained a motility of 20% (120 h, raw state). When comparisons were carried out after thawing, motility was higher in the 5°C group, achieving the best results with TT diluent (7.5%) at 102 h. However, when supravital stain and E+ tests were observed, viability and membrane integrity were well preserved even at 102 h post mortem (30 and 36%, respectively, with TT diluent at 5°C). These results suggest that frozen-thawed epididymal spermatozoa could have a low motility rate while most of them remain alive. Acrosome status was not greatly affected by storage time. In a second experiment, epididymal spermatozoa from hunted red deer stags (Cervus elaphus) were recovered at 4 and 30 h after death. The scrotal contents were stored at 20°C, because that temperature is closer to field and shipment conditions. The sperm cells were frozen with TT diluent. Post-thawing evaluation included the same parameters indicated for bull spermatozoa. The assessment of spermatozoa collected at 30 hours post mortem and then subsequently frozen and thawed indicated that at this time an acceptable motility rate (35%) and viability (39.7%) were achieved. Frozen and subsequently thawed epididymal spermatozoa showed 47.9% of membrane integrity, 59.3% of acrosome integrity and 26.5% of chromatin damage, using TT diluent. A preliminary in vivo trial demonstrated that the pregnancy rate in artificially inseminated deer decreased when sperm were obtained at 30 h post mortem. According to these results, it may be concluded that storage at 5°C is better than 20°C to obtain well preserved epididymal spermatozoa from bulls, and that TT could be a useful cryoprotectant to preserve viable and fertile sperm cells after the freezing–thawing process. Before these results can be applied to assisted reproduction programs in endangered deer species, some adaptations must be developed.

Sign in / Sign up

Export Citation Format

Share Document