Microbiology Research

17 pages, 9406 KiB

Open AccessArticle

Effect of Carotenoid Composition on Stability and Light-Induced Oxidative Damage of the LH2 Complexes Isolated from Ectothiorhodospira haloalkaliphila

by Denis V. Yanykin, Mark O. Paskhin, Sergey A. Shumeyko, Aleksandr A. Ashikhmin and Maxim A. Bolshakov

Microbiol. Res. 2025, 16(2), 36; https://doi.org/10.3390/microbiolres16020036 - 2 Feb 2025

Viewed by 257

Abstract

Earlier, it has been shown that carotenoid-dependent singlet oxygen photogeneration in LH2 of Ectothiorhodospira haloalkaliphila leads to damage to pigments and protein. Present work continues this investigation using LH2 complexes with altered carotenoid composition: carotenoid-less LH2, and LH2 complexes with incorporated neurosporene, spheroidene, [...] Read more.

Earlier, it has been shown that carotenoid-dependent singlet oxygen photogeneration in LH2 of Ectothiorhodospira haloalkaliphila leads to damage to pigments and protein. Present work continues this investigation using LH2 complexes with altered carotenoid composition: carotenoid-less LH2, and LH2 complexes with incorporated neurosporene, spheroidene, or rhodopin (LH2-Neu, LH2-Sph, or LH2-Rho, respectively). This work provides the first data on the products (hydroperoxides of organic molecules, most likely components of the protein matrix of the complexes) of the interaction of singlet oxygen with LH2 components with a modified carotenoid composition; the ability of various carotenoids to both influence the stability of LH2 and participate in oxidative damage to the complexes is assessed. It was shown that inhibition of carotenoid synthesis led to a decrease in LH2 thermal stability and reduced the light-induced oxidative damage to bacteriochlorophyll and protein. Re-incorporation of exogenous carotenoids did not return stability of the complexes but reduced the tendency of complexes to aggregate, and (in the case of LH2-Rho) reactivated both photooxidation of bacteriochlorophyll and photoproduction of organic hydroperoxides. It was concluded that carotenoids play an important role in comple x stability and are capable of inducing oxidative damage to LH2 components through singlet oxygen photogeneration. Full article

► Show Figures

Figure 1

15 pages, 1405 KiB

Open AccessArticle

Biological Control of Sclerotinia sclerotiorum on Greenhouse Lettuce Using Trichoderma koningiopsis Agg

by Snježana Topolovec-Pintarić, Ana Maria Kovaček, Olga Malev, Ivana Kušan, Neven Matočec, Ana Pošta, Lucia Pole and Armin Mešić

Microbiol. Res. 2025, 16(2), 35; https://doi.org/10.3390/microbiolres16020035 - 31 Jan 2025

Viewed by 291

Abstract

The lettuce drop or white mold is an economically important disease as the causal fungus Sclerotinia sclerotiorum can infect the lettuce at any stage of plant development. Polyphagous nature of S. sclerotiorum, the longevity of soil-borne sclerotia and air-borne ascospores makes the [...] Read more.

The lettuce drop or white mold is an economically important disease as the causal fungus Sclerotinia sclerotiorum can infect the lettuce at any stage of plant development. Polyphagous nature of S. sclerotiorum, the longevity of soil-borne sclerotia and air-borne ascospores makes the control difficult. Chemical fungicides are available only for foliar application against infections by ascospores so, the development of bio-control is of great importance. We tested antagonism of native isolate T. koningiopsis agg. (Hypocreales) (STP8) under laboratory and greenhouse environments. In vitro tests showed excellent STP8 antagonisms to S. sclerotiorum evidencing hyperparasitic activity on mycelia and sclerotia as well as antibiosis. The sclerotia were completely degraded after two months. In the greenhouse, infection of lettuce with S. sclerotiorum was reduced by treating the seedlings with an STP8 spore suspension. Uninfected plants treated with STP8 were of the best quality based on morphological parameters, confirming the ability of STP8 to promote lettuce growth. Even the infected lettuce treated with STP8 were healthier and in better condition than the control lettuce, suggesting that STP8 was also enhancing plant defense system. Full article

(This article belongs to the Collection Microorganisms and Their Incredible Potential to Face Societal Challenges)

► Show Figures

Figure 1

27 pages, 4553 KiB

Open AccessArticle

Enterobacter soli Strain AF-22b-4245: Study of the Genome and the Effect on Wheat Growth

by Ekaterina Alexeevna Sokolova, Olga Viktorovna Mishukova, Inna Viktorovna Khlistun, Irina Nikolaevna Tromenschleger, Evgeniya Vladimirovna Chumanova and Elena Nikolaevna Voronina

Microbiol. Res. 2025, 16(2), 34; https://doi.org/10.3390/microbiolres16020034 - 30 Jan 2025

Viewed by 473

Abstract

Background: In this work the plant growth-promoting (PGP) qualities of the Enterobacter soli strain AF-22b-4245 were studied, including screening tests for PGP, whole genome sequencing (WGS) and genome annotation, and greenhouse experiments on wheat. A gene table was formed that allows us to [...] Read more.

Background: In this work the plant growth-promoting (PGP) qualities of the Enterobacter soli strain AF-22b-4245 were studied, including screening tests for PGP, whole genome sequencing (WGS) and genome annotation, and greenhouse experiments on wheat. A gene table was formed that allows us to evaluate the potential PGP properties of a microorganism based on the results of genome-wide sequencing. Results: Based on the results of screening tests and genome annotation, it can be concluded that the E. soli strain AF-22b-4245 strain may have PGP properties, which consist in the ability to survive in arid and saline soils contaminated with copper, arsenic, lead, and chromium soils, form biofilms, produce phytohormones, siderophores, and solubilize phosphorus. Based on the results of experiments on wheat, the E. soli strain AF-22b-4245 increases the efficiency of mineral fertilizers; this effect persists even in conditions of drought and excess salt. It has been shown that E. soli A F22b-4245 can compensate for the lack of soluble phosphorus in the mineral fertilizer, probably by solubilizing insoluble forms in the soil. Full article

► Show Figures

Figure 1

13 pages, 1019 KiB

Open AccessArticle

Sex Differences and Pathogen Patterns in Surgically Treated Aortic Valve Endocarditis over 15 Years

by Elisa Mikus, Mariafrancesca Fiorentino, Diego Sangiorgi, Antonino Costantino, Simone Calvi, Elena Tenti, Elena Tremoli, Alberto Tripodi and Carlo Savini

Microbiol. Res. 2025, 16(2), 33; https://doi.org/10.3390/microbiolres16020033 - 29 Jan 2025

Viewed by 319

Abstract

Background: Infective endocarditis (IE) is a serious public health concern due to its high morbidity and lethality. This study investigates epidemiological trends in aortic valve endocarditis, focusing on sex-related differences in microbial etiology and surgical outcomes over a 15-year period. Methods: From January [...] Read more.

Background: Infective endocarditis (IE) is a serious public health concern due to its high morbidity and lethality. This study investigates epidemiological trends in aortic valve endocarditis, focusing on sex-related differences in microbial etiology and surgical outcomes over a 15-year period. Methods: From January 2010 to January 2024, 608 patients underwent cardiac surgery for IE at our center. Of these, 274 patients received isolated aortic valve replacement. This retrospective, single-center study analyzes these cases. Results: Despite a decline in overall aortic valve replacement surgeries, a significant increase in surgeries due to aortic valve endocarditis was observed (p < 0.001). Both sexes showed a rising incidence of aortic valve endocarditis, with females undergoing surgery at an older age, particularly in native valve cases (p = 0.008). In prosthetic valve cases, this age difference was less pronounced (p = 0.050). While sex did not influence microbial etiology in native valve endocarditis, females with prosthetic valves were more frequently infected by Streptococcus (p = 0.033). Staphylococcus aureus infections increased in native valves (p = 0.016). Conclusions: Over 15 years, surgical aortic valve endocarditis has risen in both sexes. Males are more often affected by native valve cases, while females develop it later. Neither gender nor microbial etiology independently predicts death. Full article

► Show Figures

Figure 1

12 pages, 1827 KiB

Open AccessArticle

In Vitro Evaluation of the Antiviral Properties of Exogenous mRNA Encoding the Human MxA Protein

by Marina A. Plotnikova, Ekaterina A. Romanovskaya-Romanko, Anastasia A. Pulkina, Marina A. Shuklina, Anna-Polina S. Shurygina and Sergey A. Klotchenko

Microbiol. Res. 2025, 16(2), 32; https://doi.org/10.3390/microbiolres16020032 - 25 Jan 2025

Viewed by 433

Abstract

MxA is a cytoplasmic protein induced in human cells exposed to type I and III interferons. It can inhibit various viruses, including influenza A, by blocking the early steps of the viral replication cycle. The rapid advancement of mRNA-based technology has allowed us [...] Read more.

MxA is a cytoplasmic protein induced in human cells exposed to type I and III interferons. It can inhibit various viruses, including influenza A, by blocking the early steps of the viral replication cycle. The rapid advancement of mRNA-based technology has allowed us to evaluate the antiviral activity of MxA-mRNA, encoding intracellular MxA protein, and explore its potential as a therapeutic agent. In this study, we used in vitro transfection methods to obtain functional, mature MxA-mRNA and evaluate its activity within cells. We also observed an undesirable cellular response to transfection with exogenous mRNAs, which involved interferon III induction and reduced cell viability. Nevertheless, preventive administration of MxA-mRNA led to a specific 10–80-fold decrease in influenza A and B levels in cell supernatants—an effect not observed with the control GFP-Luc-mRNA. Additionally, we investigated the antiviral activity of MxA-mRNA against RNA viruses, such as SARS-CoV-2 and both serotypes of RSV, but we could not demonstrate a significant virus-specific effect of exogenous mRNA on their replication. We believe that mRNAs that encode native antiviral proteins have great therapeutic potential. Full article

► Show Figures

Figure 1

15 pages, 4223 KiB

Open AccessCase Report

First Isolation, Molecular Identification, and Phylogenetic Characterization of A3B5 Very Virulent Infectious Bursal Disease Virus in Pullets in Chile

by Leandro Cádiz, Miguel Guzmán, Paola Rivera, Fernando Navarrete, Paulina Torres and Héctor Hidalgo

Microbiol. Res. 2025, 16(2), 31; https://doi.org/10.3390/microbiolres16020031 - 23 Jan 2025

Viewed by 543

Abstract

Infectious bursal disease virus (IBDV) is an important pathogen affecting the poultry industry worldwide. IBDV serotype 1, including classical virulent strains (cvIBDV), variant strains (varIBDV), and very virulent strains (vvIBDV), is pathogenic for chickens. IBDV mainly infects immature B-lymphocytes in the bursa of [...] Read more.

Infectious bursal disease virus (IBDV) is an important pathogen affecting the poultry industry worldwide. IBDV serotype 1, including classical virulent strains (cvIBDV), variant strains (varIBDV), and very virulent strains (vvIBDV), is pathogenic for chickens. IBDV mainly infects immature B-lymphocytes in the bursa of Fabricius, weakening the humoral immune response and leading to secondary infections and increased morbidity and mortality. The Laboratory of Avian Pathology received ten live 8-week-old pullets from a laying hen operation experiencing increased mortality, prostration, diarrhea, and sudden death. Upon necropsy, the affected birds presented swollen, hemorrhagic, and edematous bursa of Fabricius, as well as hemorrhage in the breast and thigh muscles. RT-PCR confirmed that the samples from the bursa of Fabricius were positive for IBDV. Phylogenetic analysis of the VP1 and VP2 gene nucleotide sequences classified the strain, isolated in embryonated chicken eggs, as the A3B5 genotype. Amino acid sequence analysis of the VP2 hypervariable region revealed the presence of amino acid residues commonly found in vvIBDV. Additional studies are required to investigate the epidemiological situation of this genotype in Chile and to evaluate current vaccination plans and their effectiveness against new variants. Full article

13 pages, 743 KiB

Open AccessArticle

Trends and Patterns of Antimicrobial Resistance in a Tertiary Care Hospital in Bangladesh

by Sangjukta Roy, Hridika Talukder Barua, Mohammad Julhas Sujan, Akram Hossain, Shyamal Kumar Paul, Syeda Anjuman Nasreen, Salma Ahmed, Nazia Haque, Zakir Hossain Habib, Aninda Rahman, S. M. Shahriar Rizvi, Md. Abul Hasnat, Soo Young Kwon, John Stelling, Sanjay Gautam, Alina Shaw, Florian Marks and Nimesh Poudyal

Microbiol. Res. 2025, 16(2), 30; https://doi.org/10.3390/microbiolres16020030 - 23 Jan 2025

Viewed by 536

Abstract

Introduction: Antimicrobial resistance (AMR) is a global public health issue, particularly in resource-limited, low- to middle-income countries like Bangladesh. In this study, we analyze and present four years of data on AMR from a tertiary care hospital in Bangladesh to inform policymakers and [...] Read more.

Introduction: Antimicrobial resistance (AMR) is a global public health issue, particularly in resource-limited, low- to middle-income countries like Bangladesh. In this study, we analyze and present four years of data on AMR from a tertiary care hospital in Bangladesh to inform policymakers and the wider community. Methods: In a retrospective cross-sectional study, we collected data for 4403 bacterial isolates reported between January 2017 and February 2020 at Mymensingh Medical College Hospital (MMCH), Bangladesh. All data were entered, cleaned, and analyzed using the software Stata Version-16.0, WHONET, a microbiology laboratory data management solution, and Quick Analysis of Antimicrobial Patterns and Trends (QAAPT), an AMR data visualization platform. Results: The bacteria were most commonly isolated from urine (71.66%, n = 3155), followed by pus (11.63%, n = 512), sputum (6.70%, n = 295), wound swabs (6.70%, n = 295), stool (1.91%, n = 84), endotracheal aspirate (1.20%, n = 53), and blood (0.20%, n = 9). Gram-negative bacteria predominated in all samples. Escherichia coli was the most common Gram-negative bacterium (31.30%, n = 1378), while Staphylococcus aureus was the most common Gram-positive bacterium (4.38%, n = 193). Antimicrobial susceptibility testing (AST) showed that multidrug resistance in Gram-negative bacteria such as E. coli, Klebsiella sp., and Acinetobacter sp. was common. S. aureus exhibited high resistance rates for beta-lactams, macrolides, and quinolones. In the urine samples, E. coli demonstrated high resistance to antibiotics like amoxicillin/clavulanic acid, ciprofloxacin, ceftriaxone, and cefuroxime (60–100%). Critical and high-priority pathogens as listed by the WHO constituted approximately 60% of the isolates. The AMR trends over three months showed increased resistance to amoxicillin/clavulanic acid for E. coli and to cefuroxime for Klebsiella sp. For S. aureus, the resistance to ciprofloxacin increased over three years, while the resistance to azithromycin decreased. Conclusions: There is a rise in bacterial resistance to the available antibiotics, with a significant prevalence of critical and high-priority pathogens in Bangladesh. We recommend vigilant AMR surveillance and stewardship programs to control the AMR in this country. Full article

17 pages, 1875 KiB

Open AccessArticle

Zoonotic Foodborne Infections in a Tertiary Healthcare Setting: Clinical and Epidemiological Aspects of Campylobacter and Salmonella Infection in Northern Portugal in 2010–2020

by Maria Inês Matos, Rafael Rocha, João Pinto, André Guimarães, Rita Lino, Maria Helena Rocha, Marta Patacho, Raquel Duro, Lurdes Santos and Jorge Almeida

Microbiol. Res. 2025, 16(2), 29; https://doi.org/10.3390/microbiolres16020029 - 23 Jan 2025

Viewed by 581

Abstract

This study aimed to describe the epidemiology, clinical presentation, and management of Campylobacter sp. and Salmonella sp. infections in a tertiary hospital in Northern Portugal (2010–2020) and identify factors associated with reporting, invasive disease, and hospitalization. A retrospective review included patients with Campylobacter [...] Read more.

This study aimed to describe the epidemiology, clinical presentation, and management of Campylobacter sp. and Salmonella sp. infections in a tertiary hospital in Northern Portugal (2010–2020) and identify factors associated with reporting, invasive disease, and hospitalization. A retrospective review included patients with Campylobacter sp. (2015–2020) or Salmonella sp. infections (2010–2020). Reported cases were cross-referenced with the National Epidemiological Surveillance System. A total of 742 patients were included: 342 with Campylobacter sp., 392 with non-typhoidal Salmonella (NTS), and 15 with typhoidal Salmonella (TS). Immunosuppression was present in 16.7% of cases. NTS infections were invasive in 21.4% of cases, compared to 4.0% for Campylobacter. Macrolide resistance in Campylobacter reached 10%, particularly in C. coli, while multidrug resistance (MDR) was observed in 37.8% of NTS isolates. Immunocompromised patients accounted for over 70% of relapses in Campylobacter disease. Reporting rates were low: 32.8% for NTS, 30.6% for Campylobacter, and 14.3% for TS. Reporting was associated with male sex, no immunosuppression, hospitalization, and non-MDR organisms. In conclusion, immunocompromised patients face higher risks of invasive and relapsing disease. High rates of MDR in NTS limit treatment options. Underreporting remains significant, underscoring the need for improved awareness and reporting to inform public health strategies. Full article

► Show Figures

Figure 1

Journal Menu

Journal Browser

Microbiol. Res., Volume 16, Issue 2 (February 2025) – 8 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI