Pediococcus Acidilactici Inhibit Biofilm Formation of Food-Borne Pathogens on Abiotic Surfaces

In this study,we aimed to examine the inhibitory effect of PA003,a Pediococcus acidilactici that produces lactic acid and antimicrobial peptides pediocin,on pathogenic biofilm formation on abiotic surfaces.PA003 and pathogens(Escherichia coli,Salmonella enterica serovar Typhimurium,Staphylococcus aureus and Listeria monocytogenes) were used to evaluate auto-aggregation,hydrophobicity,biofilm formation and biofilm formation inhibition on stainless steel,polyvinyl chloride and glass slides in terms of exclusion,displacement and competition.The results showed the highest auto-aggregation abilities were observed for one of the E.coli strains EAggEC(E58595) and the highest hydrophobic strain was observed with EPEC(E2348/69)(51.9%).The numbers of biofilm cells of E.coli,S.Typhimurium,S.aureus and L.monocytogenes on stainless steel,polyvinyl chloride and glass slide coupons were effectively reduced by approximately 4log CFU/coupon.These results demonstrate that lactic acid bacteria can be used as an alternative to effectively control the formation of biofilms by food-borne pathogens.

Quantum dot biosensor combined with antibody and aptamer for tracing food-borne pathogens

Due to the increasing number of food-borne diseases,more attention is being paid to food safety.Food-borne pathogens are the main cause of food-borne diseases,which seriously endanger human health,so it is necessary to detect and control them.Traditional detection methods cannot meet the requirements of rapid detection of food due to many shortcomings,such as being time-consuming,laborious or requiring expensive instrumentation.Quantum dots have become a promising nanotechnology in pathogens tracking and detection because of their excellent optical properties.New biosensor detection methods based on quantum dots are have been gradually developed due to their high sensitivity and high specificity.In this review,we summarize the different characteristics of quantum dots synthesized by carbon,heavy metals and composite materials firstly.Then,attention is paid to the principles,advantages and limitations of the quantum dots biosensor with antibodies and aptamers as recognition elements for recognition and capture of food-borne pathogens.Finally,the great potential of quantum dots in pathogen detection is summarized.

Antimicrobial effects of carnosic acid,kaempferol and luteolin on biogenic amine production by spoilage and food-borne pathogenic bacteria

Antimicrobial effects of carnosic acid,kaempferol and luteolin on biogenic amine(BA)production by five spoilage(Photobacterium damselae,Proteus mirabilis,Enterobacter cloacea,Pseudomonas luteola and Serratia liquefaciens)and five food-borne pathogenic bacteria(Staphylococcus aureus ATCC29213,Enterococcus faecalis ATCC29212,Escherichia coli ATCC25922,Salmonella Paratyphi A NCTC13 and Yersinia enterocolitica NCTC 11175)were investigated.The formation of ammonia(AMN),trimethylamine(TMA)and BAs by all bacterial strains were observed using ornithine decarboxylase broth.BAs,AMN,and TMA were determined by using high performance liquid chromatography(HPLC)method.The results showed that significant differences were observed(P≤0.05)in formation among spoilage and also food-borne bacteria.The impact of phenolic compounds on AMN,TMA and BAs production was dependent on bacterial strains.When total amount of cadaverine(CAD),putrescine(PUT),histamine(HIS)and tyramine(TYR)was considered,the phenolic compounds presented antimicrobial activity against fish spoliage bacteria and food-borne pathogens following the order;kaempferol>carnosic acid>luteolin.These phenolics have potential to be used as food preservatives.

Animals as sources of food-borne pathogens: A review

Food-producing animals are the major reservoirs for many foodborne pathogens such as Campylobacter species, non-Typhi serotypes of Salmonella enterica, Shiga toxin-producing strains of Escherichia coli, and Listeria monocytogenes. The zoonotic potential of foodborne pathogens and their ability to produce toxins causing diseases or even death are sufficient to recognize the seriousness of the situation. This manuscript reviews the evidence that links animals as vehicles of the foodborne pathogens Salmonella,Campylobacter, Shiga toxigenic E. coli, and L. monocytogenes, their impact, and their current status. We conclude that these pathogenic bacteria will continue causing outbreaks and deaths throughout the world, because no effective interventions have eliminated them from animals and food.

Antiseptic Efficacy of A Soap Made from Biosurfactants Isolated from Bacillus and Lactobacillus against Pathogenic Bacteria

The aim of our study was to use a biosurfactant produced by Bacillus and Lactobacillus isolates as an antiseptic in the formulation of local soap. A total of 60 isolates were characterized by microbiological techniques (30 Bacillus and 30 Lactobacillus) and the ability to produce biosurfactants was demonstrated by a hydrocarbon emulsification index (E24). The emulsification indexes (E24) varied from 9% to 100% for Bacillus and from 33% to 100% for Lactobacillus as well. The antagonistic assay showed that biosurfactants were able to inhibit the formation of biofilms and growth of pathogens such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhirium, Shigella boydii and Proteus mirabilis. The biosurfactant consortium (BioC) from Bacillus consortium and from Lactobacillus was able to inhibit biofilm formation and the pathogens growth. The BioC was stable to alkaline pH and the temperatures stability of Biosurfactant was ranging from 50°C to 90°C. The soap was made by the cold saponification process using one biosurfactant consortium formulated. This soap has a pH of 10 and showed good cleaning power and good foam stability. Similarly, the soap showed good antiseptic power and disinfection power against all pathogens tested. Handwashing is critical to preventing disease transmission. The persistence of pathogens in waste water was evaluated. The BioS produced showed good disinfection power against all pathogens tested. The valor of reduction on the hands and in the waste water was significantly more than compared to the control soaps used. This soap could be used in the prevention, fighting, and treatment of bacterial and viral infections.

The virulence regulator AbsR in avian pathogenic Escherichia coli has pleiotropic effects on bacterial physiology

Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin production regulation,locus A,herein renamed AbsR,a blood survival regulator),a member of the MarR(multiple antibiotic resistance regulator)transcriptional regulator family,governs the expression of capsule biosynthetic genes in human ExPEC and represents a promising druggable target for antimicrobials.However,a deep understanding of the AbsR regulatory mechanism as well as its regulon is lacking.In this study,we present a systems-level analysis of the APEC AbsR regulon using ChIP-Seq(chromatin immunoprecipitation sequencing)and RNA-Seq(RNA sequencing)methods.We found that AbsR directly regulates 99 genes and indirectly regulates 667 genes.Furthermore,we showed that:1)AbsR contributes to antiphagocytotic effects by macrophages and virulence in a mouse model for systemic infection by directly activating the capsular gene cluster;2)AbsR positively impacts biofilm formation via direct regulation of the T2SS(type II secretion system)but plays a marginal role in virulence;and 3)AbsR directly upregulates the acid tolerance signaling system EvgAS to withstand acid stress but is dispensable in ExPEC virulence.Finally,our data indicate that the role of AbsR in virulence gene regulation is relatively conserved in ExPEC strains.Altogether,this study provides a comprehensive analysis of the AbsR regulon and regulatory mechanism,and our data suggest that AbsR likely influences virulence primarily through the control of capsule production.Interestingly,we found that AbsR severely represses the expression of the type I-F CRISPR(clustered regularly interspaced short palindromic repeats)-Cas(CRISPR associated)systems,which could have implications in CRISPR biology and application.

SsdchA is a novel secretory cellobiohydrolase driving pathogenicity in Sclerotinia sclerotiorum

The necrotrophic fungus, Sclerotinia sclerotiorum, employs an array of cell wall-degrading enzymes(CWDEs), including cellulase, to dismantle host cell walls. However, the molecular mechanisms through which S. sclerotiorum degrades cellulose remain elusive. Here, we unveil a novel secretory cellobiohydrolase, SsdchA, characterized by a signal peptide and a Glyco_hydro_7(GH7) domain. SsdchA exhibits a robust expression of during early infection stages. Interestingly, colony morphology and growth rates remain unaffected across the wild-type, SsdchA deletion strains and SsdchA overexpression strains on potato dextrose agar(PDA) medium. Nevertheless, the pathogenicity and cellobiohydrolase activity decreased in the SsdchA deletion strains, but enhanced in the SsdchA overexpression strains. Moreover,the heterologous expression of SsdchA in Arabidopsis thaliana leads to reduced cellulose content and heightened susceptibility to S. sclerotiorum. Collectively, our data underscore the pivotal role of the novel cellobiohydrolase SsdchA in the pathogenicity of S. sclerotiorum.

Control of highly pathogenic avian influenza through vaccination

The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.

A novel pathogen Fusarium cuneirostrum causing common bean(Phaseolus vulgaris)root rot in China

Several fungal pathogens cause root rot of common bean,among which Fusarium spp.are the most common pathogens causing Fusarium root rot(FRR)worldwide.FRR has been becoming an increasingly severe disease of common bean in China,but the species of Fusarium spp.have remained unclear.Thus,this study was performed to identify the pathogen causing common bean root rot in Liangcheng County,Inner Mongolia,China.Nineteen Fusarium-like isolates were obtained after pathogen isolation and purification.The pathogenicity test indicated that eight isolates caused severe disease symptoms on common bean,while 11 other isolates were not pathogenic.The eight pathogenic isolates,FCL1–FCL8,were identified as Fusarium cuneirostrum by morphological characterization and phylogenetic analysis using partial sequences of EF-1α,ITS,28S,and IGS regions.Host range test showed that the representative F.cuneirostrum isolate FCL3 was also pathogenic to mung bean,while not pathogenic to adzuki bean,chickpea,cowpea,faba bean,pea,and soybean.Moreover,50 common bean and 50 mung bean cultivars were screened for resistance to FRR,and seven highly resistant or resistant cultivars of common bean were identified,while no resistant cultivars of mung bean were screened.This study revealed that F.cuneirostrum was one of common bean FRR pathogens in Inner Mongolia and it could induce mung bean root rot as well.To our knowledge,this is the first report of F.cuneirostrum causing FRR of common bean in China.

Distribution of pathogenic bacteria and antimicrobial sensitivity of eye infections in Suzhou

AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial drugs.METHODS:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were analyzed.RESULTS:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were fungi.Gram-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at 0.Gram-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at 0.Comparison of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive bacteria.The distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye parts.Besides,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal infections.CONCLUSION:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and fungi.Considering the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.

Research Progress on Pathogens of Main Diseases of Dictyophora rubrovalvata and Their Occurrence

Dictyophora rubrovalvata is an edible fungus with rich nutritional value.It contains various nutrients and bioactive components,and has immunomodulation,anti-tumor,anti-oxidation,anti-fatigue,anti-aging,anti-inflammation and alcoholic hepatitis-protection effects.With the continuous expansion of planting area of Dictyophora,the disease problem has become a major problem affecting the development of Dictyophora industry.In this paper,the pathogens,harmful symptoms and causes of main diseases in Dictyophora were summarized,so as to provide reference for comprehensive control of Dictyophora diseases and promote the high-quality development of Dictyophora industry.

RDH12-associated retinal degeneration caused by a homozygous pathogenic variant of 146C>T and literature review

AIM:To describe the clinical,electrophysiological,and genetic features of an unusual case with an RDH12 homozygous pathogenic variant and reviewed the characteristics of the patients reported with the same variant.METHODS:The patient underwent a complete ophthalmologic examination including best-corrected visual acuity,anterior segment and dilated fundus,visual field,spectral-domain optical coherence tomography(OCT)and electroretinogram(ERG).The retinal disease panel genes were sequenced through chip capture high-throughput sequencing and Sanger sequencing was used to confirm the result.Then we reviewed the characteristics of the patients reported with the same variant.RESULTS:A 30-year male presented with severe early retinal degeneration who complained night blindness,decreased visual acuity,vitreous floaters and amaurosis fugax.The best corrected vision was 0.04 OD and 0.12 OS,respectively.The fundus photo and OCT showed bilateral macular atrophy but larger areas of macular atrophy in the left eye.Autofluorescence shows bilateral symmetrical hypo-autofluorescence.ERG revealed that the amplitudes of a-and b-wave were severely decreased.Multifocal ERG showed decreased amplitudes in the local macular area.A homozygous missense variant c.146C>T(chr14:68191267)was found.The clinical characteristics of a total of 13 patients reported with the same pathologic variant varied.CONCLUSION:An unusual patient with a homozygous pathogenic variant in the c.146C>T of RDH12 which causes late-onset and asymmetric retinal degeneration are reported.The clinical manifestations of the patient with multimodal retinal imaging and functional examinations have enriched our understanding of this disease.

Resistance of Microbial Community of Artemisia annua L.to Pathogenic Fungi

[Objectives]This paper was to figure out whether the dominant bacterial community has the role and effect of bacterial community and its defense mechanism against potential pathogenic fungi in Artemisia annua,and thus establish a systematic model of bacteria-fungus-plant.[Methods]Fifty-eight strains of bacteria and one strain of pathogenic fungi,Globisporangium ultimatum,were used for the experiments.These 58 bacterial strains were assembled into a bacterial community,and the bacteria with abundance in the top 1%were reassembled into a dominant bacterial community as measured by 16S rDNA.[Results]The growth of A.annua seedlings inoculated with bacterial communities and pathogenic fungi or dominant bacterial communities and pathogenic fungi was significantly better than that of A.annua seedlings inoculated with pathogenic fungi during in vitro confrontation,which was evident in both enzymatic and non-enzymatic antioxidant assays.[Conclusions]The results suggest that the dominant bacterial community has a crucial role as a representative core microbial community of synthetic bacterial community,which can protect plants by interfering with the growth of phytopathogenic fungi mediated by chemical signals,and can be used as the main synthetic community of biocides to achieve the effect of biocontrol.

A Natural Catalytic Converter® for Continuously Inactivating Air and Surface Pathogens with More Effect than Ventilation and Filtration

Study Objective: The purpose of the study is to present independent laboratory testing for a novel technology in air and on surfaces. Since 2020, public health goals have focused on improving indoor air quality. This includes protection from airborne pathogens, such as tuberculosis, RSV, SARS-CoV-2, common cold or influenza viruses, measles, and others. Engineering controls are highly effective at reducing hazardous pathogens found in indoor air and from recontamination of surfaces. This occurs from a continuous cycle of settling of small, sustained airborne pathogens, which may become dehumidified, becoming airborne again, carried by room air currents around indoor spaces, then repeating the cycle. Methods: The novel technology utilizes a catalytic process to produce safe levels of hydrogen peroxide gas that are effective in reducing pathogens in the air and on surfaces. Air testing was performed with the MS2 bacteriophage, the test organism for ASHRAE standard 241, and methicillin-Resistant Staphylococcus aureus (MRSA). Surface testing was performed with SARS-COV-2 (Coronavirus COVID-19) and H1N1 (Influenza). Typical ventilation and filtration does not effectively remove disbursed pathogens from the entire facility, due to inconsistent air circulation and surface deposits of pathogens. Results: MS2 was reduced by 99.9%;MRSA was reduced by 99.9%;SARS-CoV-2 was reduced by 99.9%;H1N1 was reduced by 99.9%. Conclusion: This novel catalytic converter reduces a variety of pathogens in the air (99%) and on surfaces (99%), by actively disinfecting with the introduction of gaseous hydrogen peroxide. This active disinfection provides a strong solution for protecting the entire facility and its occupants.

Distribution and Drug Resistance Analysis of 2287 Strains of Pathogenic Bacteria in Children’s Blood Culture

Background: Bloodstream infection is a serious infectious disease. In recent years, the drug resistance of pathogenic bacteria to commonly used anti-infective drugs has been widely concerned, which also makes the treatment of bloodstream infection face severe challenges. Objective: To explore the distribution characteristics of blood culture-positive pathogens and the resistance to antibacterial drugs, so as to provide clinicians with accurate laboratory evidence, so as to guide clinicians to rationally apply antibiotics, improve clinical treatment effects, and reduce the emergence of drug-resistant strains. Methods: From January 2019 to June 2022, 2287 positive blood culture specimens of patients in Guangzhou Women and Children’s Medical Center were retrospectively analyzed, and the proportion of different pathogenic bacteria, the distribution of pathogenic bacteria in different departments, and the multi-drug resistance of different pathogenic bacteria were counted. Results: Among the 2287 blood culture positive samples, 1560 strains (68.20%) of gram-positive bacteria and 727 strains (31.80%) of gram-negative bacteria were strained. The top three departments in the distribution of pathogenic bacteria were pediatric intensive care unit (600 strains), pediatric internal medicine (514 strains), and pediatric emergency comprehensive ward (400 strains). The pathogens with high detection rates were: Staphylococcus epidermidis (24.09%), Staphylococcus humans (23.74%), Escherichia coli (13.21%) and Klebsiella pneumoniae (8.71%). The pathogens with high multi-drug resistance rates were: Streptococcus pneumoniae (93%), Staphylococcus epidermidis (83.76%), Enterobacter cloacae (75.61%) and Staphylococcus humans (62.43%). Conclusion: In our hospital, gram-positive bacteria were the main pathogenic bacteria in the blood culture of children patients. The children’s intensive care unit was the department with the largest distribution of pathogenic bacteria, and the multiple drug resistance rate of Streptococcus pneumoniae was the highest.

Review on microbial metabolomics of probiotics and pathogens:Methodologies and applications

In recent years,microbial metabolomics,a new field that has attracted wide attention,provides a map of metabolic pathways and clarifies the interaction mechanism between microorganisms and hosts.Many microorganisms are found in the human intestine,oral cavity,vagina,etc.Probiotics could maintain the good health of the host,while pathogens and an imbalance of bacterial flora lead to a series of diseases of the body and mind.Metabolomics is a science for qualitative and quantitative analysis of all metabolites in an organism or biological system,which could provide key information to understand the related metabolic pathways and associated changes.This approach analyzes the final products of cellular regulatory processes,the level of which can be regarded as the ultimate response of the biological system to genetic or environmental changes.Microbial metabolomics has been widely used in different research fields,such as microbial phenotypic classification,mutant screening,metabolic pathways,microbial metabolic engineering,fermentation engineering monitoring and optimization,microbial environmental pollution,and so on.However,there are only a few reviews on microbial metabolomics of probiotics and pathogens.This review summarizes the main methodologies,including sample preparation,identification of metabolites,data processing,and analysis.Recent applications in microbial metabolomics of probiotics and pathogens are also described.This paper first summarized the research progress and application of microbial metabolomics from two aspects:probiotics and pathogenic bacteria.Probiotics and pathogenic bacteria do not exist independently most of the time;hence,these were reviewed in the research field of coexistence of probiotics and pathogenic bacteria,which was subdivided into important microbial research fields closely related to human health,including the human gut,oral cavity,food,and nutrition-related microorganisms.Then,the main problems and trends associated with microbial metabolomics are discussed.

Identification and functional analyses of a novel FOXL2 pathogenic variant causing blepharophimosis, ptosis, and epicanthus inversus syndrome

AIM: To discover the molecular pathogenic basis of the blepharophimosis, ptosis, and epicanthus inversus syndrome(BPES), and to predict the clinical subtype according to in vitro experiments, which is significant to the prognosis.METHODS: A 3-year-old sporadic female patient with typical clinical manifestations of BPES was enrolled. The coding region of forkhead box L2(FOXL2) gene was sequenced, and the functional assays were performed in vitro by Western blotting, subcellular localization experiment, luciferase reporter assay, and quantitative realtime polymerase chain reaction.RESULTS: A novel FOXL2 point pathogenic variant(c.274G>T) was detected, resulting in a truncated protein(p.E92*). Functional studies demonstrated that the FOXL2 pathogenic variant induced the subcellular mislocalization and the abnormal transcriptional activity on promoters of the steroidogenic acute regulatory protein(StAR or STARD1) gene and the odd-skipped related 2 transcription factor(OSR2) gene.CONCLUSION: A novel pathogenic variant is identified to expand the spectrum of the known FOXL2 mutations. The in vitro experiments provide reference data and more insights to the molecular pathogenesis of BPES. The predicted high risk of ovarian insufficiency makes it significant for the patient enrolled to have further follow-up and therapy concerning female endocrinology.

The Role of Biosynthesized Metallic and Metal Oxide Nanoparticles in Combating Anti-Microbial Drug Resilient Pathogens

Because of their high efficiency, antibiotics have long been the primary treatment for infections, but the rise of drug-resistant pathogens has become a therapeutic concern. Nanoparticles, as novel biomaterials, are currently gaining global attention to combat them. Drug-resistant diseases may need the use of nanoparticles as a viable therapeutic option. By altering target locations and enzymes, decreasing cell permeability, inactivating enzymes, and increasing efflux by overexpressing efflux pumps, they can bypass conventional resistance mechanisms. Therefore, understanding how metal and metal oxide nanoparticles affect microorganisms that are resistant to antimicrobial drugs is the main objective of this review. Accordingly, the uses of metal and metal oxide nanoparticles in the fight against drug-resistant diseases appear promising. However, their mechanism of action, dose, and possible long-term effects require special attention and future research. Furthermore, repeated use of silver nanoparticles may cause gram-negative microorganisms to acquire resistance, necessitating additional study.

Evaluation under Semi-Controlled Conditions of the Pathogenicity of Three Isolates of Phaeoisariopsis personata (Berk. & M.A Curt.)

Peanut (Arachis hypogaea L.) late leaf spot is an important disease caused by Phaeoisariopsis personata (Berk. Et M. A Curt.). This fungus is responsible for the most damaging leaf spots in peanut production. The present experiment was undertaken to evaluate the pathogenic variability of Phaeoisariopsis personata in Burkina Faso. To this end, detached leaves and healthy plants of three peanut varieties were inoculated. Isolates I3TF, I2TG and I1TK of the pathogen (105 conidia/ml), collected respectively in the western, central and eastern agroecological zones of country, were used. The inoculated leaves were kept in Petri dishes on moist blotting paper and stored in the laboratory during the experimental period. The inoculated plants were grown under glass in pots containing a mixture of sterilized sand and clay. The development of disease was monitored and severity was scored every 15 days using rating scale. The results obtained in the laboratory and in the greenhouse revealed that there is pathogenic variability in the isolates tested. Indeed, for each variety, the highest severity score was recorded in plants inoculated with isolate I3TF and the lowest severity score with isolate I1TG. In the laboratory the severity scores ranged from 6.76 to 8.80 in TS32-1, 6.18 to 8.29 in SH70P and 5.98 to 7.92 in PC79-79. In the greenhouse, the average severity scores ranged from 5.61 to 8.33 in TS32-1, from 5.19 to 8.00 in SH70P, from 4.90 to 7.50 in PC79-79. Thus, the variety TS32-1 was the most susceptible to all three isolates of the pathogen.