Pathogenic potential and phytotoxic effects of Coniolariella gamsii Iran 2506C on Iranian knapweed (Centaurea depressa)

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

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Pathogenic potential of Parabacteroides distasonis revealed in a splenic abscess case: a truth unfolded

BMJ Case Reports ◽

10.1136/bcr-2020-236701 ◽

2020 ◽

Vol 13 (12) ◽

pp. e236701

Author(s):

Anitha Gunalan ◽

Rakhi Biswas ◽

Balamurugan Sridharan ◽

Thirthar Palanivelu Elamurugan

Keyword(s):

Abdominal Pain ◽

Case Report ◽

Antimicrobial Therapy ◽

Splenic Abscess ◽

Rare Entity ◽

Normal Flora ◽

Pathogenic Role ◽

Pathogenic Potential ◽

Open Splenectomy

Splenic abscess is a rare entity, however if unrecognised or left untreated, it is invariably fatal. We herein report a case of splenic abscess in a 40-year-old man presenting with fever, left-sided abdominal pain, altered sensorium and vomiting. On clinical examination, hepatosplenomegaly was noted and the ultrasound of the abdomen showed multiple hypoechoic regions in the upper pole of spleen, and the diagnosis of splenic abscess was made. The patient received antimicrobial therapy and underwent an open splenectomy with full recovery. Pus aspirated from the splenic abscess grew an unusual organism named Parabacteroides distasonis. In the literature, there are only a few recorded cases of P. distasonis causing splenic abscess. Through this case report, we would like to emphasise the pathogenic role of P. distasonis in causing clinical disease, as this organism is typically known to constitute a part of the normal flora.

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Detection of three pandemic causing coronaviruses from non-respiratory samples: systematic review and meta-analysis

Scientific Reports ◽

10.1038/s41598-021-95329-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chandan Mishra ◽

Suneeta Meena ◽

Jitendra Kumar Meena ◽

Suman Tiwari ◽

Purva Mathur

Keyword(s):

Systematic Review ◽

Detection Rate ◽

Meta Analysis ◽

Total Sample ◽

Urine Samples ◽

Pathogenic Potential ◽

Clinical Specimens ◽

Qrt Pcr ◽

Corona Virus ◽

Positive Rate

AbstractSARS-CoV-2 has posed an unprecedented challenge to the world. Pandemics have been caused previously by viruses of this family like Middle East Respiratory Corona Virus (MERS CoV), Severe Acute Respiratory Syndrome Corona Virus (SARS CoV). Although these viruses are primarily respiratory viruses, but they have been isolated from non-respiratory samples as well. Presently, the detection rate of SARS‐CoV‐2 RNA from different clinical specimens using Real Time Reverse Transcriptase Polymerized Chain Reaction (qRT‐PCR) after onset of symptoms is not yet well established. Therefore, the aim of this systematic review was to establish the profile of detecting SARS‐CoV‐2, MERS CoV, SARS CoV from different types of clinical specimens other than the respiratory using a standard diagnostic test (qRT‐PCR). A total of 3429 non-respiratory specimens were recorded: SARS CoV (total sample—802), MERS CoV (total sample—155), SARS CoV-2 (total sample—2347). Out of all the samples studied high positive rate was seen for saliva with 96.7% (14/14; 95% CI 87.6–100.0%) for SARS CoV and 57.5% (58/250; 95% CI − 1.2 to 116.2%) for SARS CoV-2, while low detection rate in urine samples for SARS CoV-2 with 2.2% (8/318; 95% CI 0.6–3.7%) and 9.6% (12/61; 95% CI − 0.9 to 20.1%) for SARS CoV but there was relatively higher positivity in urine samples for MERS CoV with detection rate of 32.4% (2/38; 95% CI − 37.3 to 102.1%). In Stool sample positivity was 54.9% (396/779; 95% CI 41.0–68.8%), 45.2% (180/430; 95% CI 28.1–62.3%) and 34.7% (4/38; 95% CI − 29.5 to 98.9%) for SARS CoV-2, MERS CoV, and SARS CoV, respectively. In blood sample the positivity was 33.3% (7/21; 95% CI 13.2–53.5%), 23.7% (42/277; 95% CI 10.5–36.9%) and 2.5% (2/81; 95% CI 0.00–5.8%) for MERS CoV, SARS CoV-2 and SARS CoV respectively. SARS‐CoV‐2 along with previous two pandemic causing viruses from this family, were highly detected stool and saliva. A low positive rate was recorded in blood samples. Viruses were also detected in fluids along with unusual samples like semen and vaginal secretions thus highlighting unique pathogenic potential of SARS‐CoV‐2.

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Root damages induced by extended phytotoxic effects of cadmium pre-exposure against subsequent lindane uptake in rice seedlings

Environmental and Experimental Botany ◽

10.1016/j.envexpbot.2021.104553 ◽

2021 ◽

pp. 104553

Author(s):

Shidi Huang ◽

Li Tan ◽

Hong Zhu ◽

G. Daniel Sheng

Keyword(s):

Rice Seedlings ◽

Phytotoxic Effects

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Locally Available Organic Waste for Counteracting Strawberry Decline in a Mountain Specialized Cropping Area

Sustainability ◽

10.3390/su13073964 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3964

Author(s):

Sebastian Soppelsa ◽

Luisa Maria Manici ◽

Francesco Caputo ◽

Massimo Zago ◽

Markus Kelderer

Keyword(s):

Field Experiment ◽

Fungal Pathogens ◽

Positive Impact ◽

Cropping Systems ◽

Fruit Trees ◽

Yield Reduction ◽

Marketable Yield ◽

Bacterial Populations ◽

Anaerobic Digestate ◽

Phytotoxic Effects

Crop decline caused by soil borne fungal pathogens affects specialized cropping systems such as fruit trees and strawberry. A study was carried out to investigate the effectiveness of pre-plant application of waste-derived biomasses in strawberry (Fragaria × ananassa) to reduce that phenomenon. A field experiment was carried out in an alpine strawberry specialized valley in South Tyrol (Italy), in a long term cultivated field selected for yield reduction over recent years. In July 2018, one month before strawberry transplanting, a field experiment with four soil treatments was set up: anaerobic digestate (solid fraction) of liquid manure, compost from anaerobic digestate of organic fraction of municipal solid waste (OFMSW), untreated control and Dazomet as chemical control. Plants were grown for two cycles (2019 and 2020). Dazomet always gave a significant (over 50%) increase in marketable yield per plant in both the years, anaerobic digestates did not improve strawberry production; compost from OFMSW gave phytotoxic effects in the first year, but improved strawberry yield like Dazomet in the second. Changes of rhizosphere bacterial populations and difference in root pathogen abundance, especially that of Dactylonectria torresensis, were correlated to the crop response to treatments. Findings suggest that waste-derived biomasses are a promising eco-friendly option for counteracting strawberry yield decline. Their positive impact was mostly linked to functional improvements induced by microbial variations. However, the use of such organic amendment requires careful evaluation of composition, doses and above all application times to reduce phytotoxic effects that in some cases can occur in the first months after application.

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The growing repertoire of genetic tools for dissecting chlamydial pathogenesis

Pathogens and Disease ◽

10.1093/femspd/ftab025 ◽

2021 ◽

Author(s):

Arkaprabha Banerjee ◽

David E Nelson

Keyword(s):

Genetic Engineering ◽

Intracellular Bacteria ◽

Human Pathogens ◽

Pathogenic Potential ◽

Host Preferences ◽

Genetic Tools ◽

Obligate Intracellular ◽

Obligate Intracellular Bacteria ◽

Multiple Species

Abstract Multiple species of obligate intracellular bacteria in the genus Chlamydia are important veterinary and/or human pathogens. These pathogens all share similar biphasic developmental cycles and transition between intracellular vegetative reticulate bodies and infectious elementary forms, but vary substantially in their host preferences and pathogenic potential. A lack of tools for genetic engineering of these organisms has long been an impediment to the study of their biology and pathogenesis. However, the refinement of approaches developed in C. trachomatis over the last ten years, and adaptation of some of these approaches to other Chlamydia spp. in just the last few years, has opened exciting new possibilities for studying this ubiquitous group of important pathogens.

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MetR-Regulated Vibrio cholerae Metabolism Is Required for Virulence

mBio ◽

10.1128/mbio.00236-12 ◽

2012 ◽

Vol 3 (5) ◽

Cited By ~ 28

Author(s):

Ryan W. Bogard ◽

Bryan W. Davies ◽

John J. Mekalanos

Keyword(s):

Amino Acid ◽

Vibrio Cholerae ◽

Virulence Factor ◽

Current Knowledge ◽

Intestinal Colonization ◽

Wild Type ◽

Pathogenic Potential ◽

Content Type ◽

Mouse Intestine

ABSTRACTLysR-type transcriptional regulators (LTTRs) are the largest, most diverse family of prokaryotic transcription factors, with regulatory roles spanning metabolism, cell growth and division, and pathogenesis. Using a sequence-defined transposon mutant library, we screened a panel ofV. choleraeEl Tor mutants to identify LTTRs required for host intestinal colonization. Surprisingly, out of 38 LTTRs, only one severely affected intestinal colonization in the suckling mouse model of cholera: the methionine metabolism regulator, MetR. Genetic analysis of genes influenced by MetR revealed thatglyA1andmetJwere also required for intestinal colonization. Chromatin immunoprecipitation of MetR and quantitative reverse transcription-PCR (qRT-PCR) confirmed interaction with and regulation ofglyA1, indicating that misregulation ofglyA1is likely responsible for the colonization defect observed in themetRmutant. TheglyA1mutant was auxotrophic for glycine but exhibited wild-type trimethoprim sensitivity, making folate deficiency an unlikely cause of its colonization defect. MetJ regulatory mutants are not auxotrophic but are likely altered in the regulation of amino acid-biosynthetic pathways, including those for methionine, glycine, and serine, and this misregulation likely explains its colonization defect. However, mutants defective in methionine, serine, and cysteine biosynthesis exhibited wild-type virulence, suggesting that these amino acids can be scavenged in vivo. Taken together, our results suggest that glycine biosynthesis may be required to alleviate an in vivo nutritional restriction in the mouse intestine; however, additional roles for glycine may exist. Irrespective of the precise nature of this requirement, this study illustrates the importance of pathogen metabolism, and the regulation thereof, as a virulence factor.IMPORTANCEVibrio choleraecontinues to be a severe cause of morbidity and mortality in developing countries. Identification ofV. choleraefactors critical to disease progression offers the potential to develop or improve upon therapeutics and prevention strategies. To increase the efficiency of virulence factor discovery, we employed a regulator-centric approach to multiplex our in vivo screening capabilities and allow whole regulons inV. choleraeto be interrogated for pathogenic potential. We identified MetR as a new virulence regulator and serine hydroxymethyltransferase GlyA1 as a new MetR-regulated virulence factor, both required byV. choleraeto colonize the infant mouse intestine. Bacterial metabolism is a prerequisite to virulence, and current knowledge of in vivo metabolism of pathogens is limited. Here, we expand the known role of amino acid metabolism and regulation in virulence and offer new insights into the in vivo metabolic requirements ofV. choleraewithin the mouse intestine.

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Proteinase and phospholipase activities and development at different temperatures of yeasts isolated from bovine milk

Journal of Dairy Research ◽

10.1017/s0022029911000434 ◽

2011 ◽

Vol 78 (4) ◽

pp. 385-390 ◽

Cited By ~ 6

Author(s):

Priscilla A Melville ◽

Nilson R Benites ◽

Monica Ruz-Peres ◽

Eugenio Yokoya

Keyword(s):

Dairy Products ◽

Room Temperature ◽

Bovine Milk ◽

Raw Milk ◽

Pathogenic Potential ◽

Proteinase Production ◽

Different Temperatures ◽

Quality Of Milk ◽

Means Of Transmission

The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

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Could Gnomoniopsis castaneae Be Used as a Biological Control Agent against Insect Pests?

Applied Sciences ◽

10.3390/app11094066 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4066

Author(s):

Spiridon Mantzoukas ◽

Ioannis Lagogiannis ◽

Aristeidis Ntoukas ◽

George T. Tziros ◽

Konstantinos Poulas ◽

...

Keyword(s):

Biocontrol Agent ◽

Insect Pests ◽

Biological Control Agent ◽

Brown Rot ◽

Control Agent ◽

Effective Control ◽

Mortality Factor ◽

Perennial Crop ◽

Gall Wasp ◽

Pathogenic Potential

Gnomoniopsis castaneae is the cause of the chestnut brown rot but has been also regarded as an important mortality factor for the chestnut gall wasp Dryocosmus kuriphilus. The question to whether G. castaneae could serve as a natural biocontrol agent against insect pests is investigated in the present study. We used three serious insect pests as experimental model insects: Plodia interpuctella and Trogoderma granarium, which are important pests of stored products, and Myzus persicae, a cosmopolitan, serious pest of annual and perennial crop plants. Although chemical pesticides represent effective control means, they are also related to several environmental and health risks. In search for alternative pest management methods, scientific interest has been focused, inter alia, on the use of entomopathogenic fungi. While Isaria fumosorosea has long been recognized as an effective control agent against several pests, G.castaneae has been very little studied. The present study examined whether and to what extent G. castaneae and I. fumosorosea exhibit insecticidal activity against fourth-instar larvae of P. interpunctella and T. granarium and adults of M. persicae. Mortality was examined in interrelation with dosage and time exposure intervals. Both fungi exhibited pesticidal action. However, G. castaneae induced noteworthy mortality only at very high doses. In general, we concluded that G. castaneae failed to cause high insect pathogenicity at normal doses and may not be an efficient biocontrol agent compared with other entomopathogens. On the other hand, our study reiterates the pathogenic potential of I. fumosorosea. More studies are needed to further our insight into the potential of EF species as a component of IPM.

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