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Plant Disease Jun 2024Dragon fruit (Selenicereus undatus) is a valuable fruit crop in tropical and subtropical regions. It is renowned for its nutritional benefits, such as high sodium,...
Dragon fruit (Selenicereus undatus) is a valuable fruit crop in tropical and subtropical regions. It is renowned for its nutritional benefits, such as high sodium, potassium, and vitamin levels, and as a source of prebiotics and antioxidants (Balendres et al. 2019). In July 2023, anthracnose symptoms on stems were detected on dragon fruit plants in Jeju, South Korea. The typical anthracnose symptoms, such as sunken necrotic lesions (5-20 mm in diameter), were seen on the mature stems. The disease incidence ranged from 10% to 12% among the three surveyed greenhouses. To isolate the causative organism, infected stem samples were surface sterilized, cut into small pieces, and placed on potato dextrose agar (PDA). After two days of incubation at 24ºC, white hyphae appeared on the PDA around the plant tissues. Isolates CNU H23009 and CNU H23010 were purified from a single hypha under a stereoscope (e-Xtra Figure 1). Conidial morphology was examined from two-day-old fungal cultures grown on V8 juice agar. The conidia were transparent, aseptate, cylindrical to clavate, with a rounded apex and base, and measured 11.9 - 16.85 × 5.17 - 6.91 μm (mean = 15.28 × 5.93 μm, n = 30). No appressoria was observed. Morphological characteristics indicated the isolates were Colletotrichum sp. matching the description of the C. gloeosporioides species complex (Weir et al. 2012). To further identify the isolates, genomic DNA was extracted and the ribosomal internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and actin (ACT) were amplified using ITS1/ITS4, GDF/GDR, and ACT-512F/ACT-783R, respectively (Weir et al. 2012). Based on phylogenetic analysis, the isolates clustered with C. aenigma (strains ICMP18608, ICMP18686, CSH2, and QSG1), with 71% bootstrap support, as determined using the maximum parsimony method in PAUP 4.0 (e-Xtra Figure 2). Based on morphological and molecular characteristics, isolates were identified as C. aenigma. Sequences of CNU H23009 and CNU H23010 were deposited in GenBank with accession numbers OR535144 and OR535145 for ITS, OR540725 and OR540726 for GAPDH, and OR540723 and OR540724 for ACT. The pathogenicity was tested on healthy dragon fruit stems using wound inoculation with mycelial plugs of the CNU H23009 isolate. Controls were inoculated with PDA plugs. The plants were covered with plastic bags to maintain humidity and incubated in a greenhouse at 25ºC. After two days, necrotic spots had developed on the inoculated tissues; after four days, black, irregular, and sunken necrotic lesions similar to those seen in the field were observed. No symptoms occurred in the controls. C. aenigma was re-isolated from the artificially inoculated plants and re-identified based on conidial morphology. The pathogenicity test was repeated three times with three replications for each treatment. Previous studies have reported that C. aenigma, C. gloeosoporioides, C. siamense, C. truncatum, and C. karsti cause anthracnose in dragon fruit. However, C. aenigma has been reported only in Thailand (Balendres et al. 2019; Meetum et al. 2015). To our knowledge, this is the first report of C. aenigma causing anthracnose in dragon fruit in Korea.
PubMed: 38916904
DOI: 10.1094/PDIS-09-23-1894-PDN -
Emerging Infectious Diseases Jul 2024Borrelia miyamotoi is an emerging tickborne pathogen that has been associated with central nervous system infections in immunocompromised patients, albeit infrequently....
Borrelia miyamotoi is an emerging tickborne pathogen that has been associated with central nervous system infections in immunocompromised patients, albeit infrequently. We describe a case-patient in Minnesota, USA, who had meningeal symptoms of 1 month duration. B. miyamotoi infection was diagnosed by Gram staining on cerebrospinal fluid and confirmed by sequencing.
Topics: Humans; Borrelia; Minnesota; Meningoencephalitis; Male; Borrelia Infections; Anti-Bacterial Agents; Middle Aged; Acute Disease; Female
PubMed: 38916722
DOI: 10.3201/eid3007.231611 -
International Journal of... Apr 2024Nocardiosis is an opportunistic infection that affects both immunocompromised as well as immunocompetent patients. The main infections occur as soft tissue and lung...
Nocardiosis is an opportunistic infection that affects both immunocompromised as well as immunocompetent patients. The main infections occur as soft tissue and lung infections although they might disseminate to various organs. This is a case study aimed to reflect the severity of the disease and the patient's risk factors associated with the infection. A sputum sample was collected from tuberculosis (TB) suspects for culture. Nocardia-like colonies were isolated, purified, and sent to BGI Company (Hongkong, China). Standard forward sequencing of 16S rRNA was done by ABI Genetic Analyzer (Applied Biosystems). Sequence alignment and nucleotide basic local alignment search tool (BLAST) were done using National Center for Bioinformatics (NCBI) Nucleotide BLAST. Biochemical identification to the colonies was done using an automation system (BD Phoenix™) to confirm the identification. Nocardia paucivorans was identified from the TB suspect. Risk factors were identified as extensive contact to dust, absence of primary care units with complete facilities, and old age. Since the infection of the lungs caused by Nocardia might be similar to pulmonary TB, this case report highlights the importance of accurate diagnosis and identification procedures to differentiate between the two.
Topics: Humans; Nocardia Infections; Nocardia; Male; Fatal Outcome; Sputum; RNA, Ribosomal, 16S; Middle Aged; Respiratory Tract Infections; Gold; Risk Factors; Tuberculosis, Pulmonary
PubMed: 38916396
DOI: 10.4103/ijmy.ijmy_129_23 -
International Journal of... Apr 2024Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and...
BACKGROUND
Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and Mycobacterium tuberculosis, little information exists on other species. The culture of these species, a real challenge, especially in developing countries like Cote d'Ivoire, limits their identification. However, there are reports in literature of infections caused by these mycobacteria, and few species have never been described in human or animal infections. These are difficult cases to treat because of their resistance to most antituberculosis antibiotics. The aim of our work was to study the diversity of potentially pathogenic mycobacterial species in wastewater drainage channels in different townships and in two hospital effluents in the city of Abidjan.
METHODS
Wastewater samples were cultured, followed by conventional polymerase chain reaction (PCR) targeting mycobacterial 16S ribonucleic acid (16S RNA) using PA/MSHA primers. 16 S RNA identified were sequenced by Sanger techniques. Sequences obtained were analyzed, and a phylogenic tree was built.
RESULTS
Fast-growing mycobacteria, including Mycobacterium fortuitum, Mycobacterium phocaicum, Mycobacterium sp., and others presence, were confirmed both by culture and molecular techniques. M. fortuitum strain was the same in effluents of the Treichville University Hospital and in the wastewater of the township of Koumassi. New species never isolated in Côte d'Ivoire, such as M. phocaicum, have been identified in wastewater of the township of Yopougon.
CONCLUSION
This study showed that the sewer network in the city of Abidjan is colonized by both potentially pathogenic mycobacteria and saprophytic environmental mycobacteria.
Topics: Cote d'Ivoire; Phylogeny; RNA, Ribosomal, 16S; Humans; Nontuberculous Mycobacteria; Wastewater; Polymerase Chain Reaction; DNA, Bacterial; Mycobacterium
PubMed: 38916386
DOI: 10.4103/ijmy.ijmy_96_24 -
Microbiology Spectrum Jun 2024
PubMed: 38916351
DOI: 10.1128/spectrum.00132-24 -
Microbiology Spectrum Jun 2024This study aimed to investigate the presence of antimicrobial resistance determinants (ARDs) in the Neanderthal microbiome through meticulous analysis of metagenomic...
UNLABELLED
This study aimed to investigate the presence of antimicrobial resistance determinants (ARDs) in the Neanderthal microbiome through meticulous analysis of metagenomic data derived directly from dental calculus and fecal sediments across diverse Neanderthal sites in Europe. Employing a targeted locus mapping approach followed by a consensus strategy instead of an assembly-first approach, we aimed to identify and characterize ARDs within these ancient microbial communities. A comprehensive and redundant ARD database was constructed by amalgamating data from various antibiotic resistance gene repositories. Our results highlighted the efficacy of the KMA tool in providing a robust alignment of ancient metagenomic reads to the antibiotic resistance gene database. Notably, the KMA tool identified a limited number of ARDs, with only the 23S ribosomal gene from the dental calculus sample of Neanderthal remains at Goyet Troisieme Caverne exhibiting ancient DNA (aDNA) characteristics. Despite not identifying ARDs with typical ancient DNA damage patterns or negative distance proportions, our findings suggest a nuanced identification of putative antimicrobial resistance determinants in the Neanderthal microbiome's genetic repertoire based on the taxonomy-habitat correlation. Nevertheless, our findings are limited by factors such as environmental DNA contamination, DNA fragmentation, and cytosine deamination of aDNA. The study underscores the necessity for refined methodologies to unlock the genomic assets of prehistoric populations, fostering a comprehensive understanding of the intricate dynamics shaping the microbial landscape across history.
IMPORTANCE
The results of our analysis demonstrate the challenges in identifying determinants of antibiotic resistance within the endogenous microbiome of Neanderthals. Despite the comprehensive investigation of multiple studies and the utilization of advanced analytical techniques, the detection of antibiotic resistance determinants in the ancient microbial communities proved to be particularly difficult. However, our analysis did reveal the presence of some authentic ancient conservative genes, indicating the preservation of certain genetic elements over time. These findings raise intriguing questions about the factors influencing the presence or absence of antibiotic resistance in ancient microbial communities. It could be speculated that the spread of current antibiotic resistance, which has reached alarming levels in modern times, is primarily driven by anthropogenic factors such as the widespread use and misuse of antibiotics in medical and agricultural practices.
PubMed: 38916350
DOI: 10.1128/spectrum.02662-23 -
Frontiers in Veterinary Science 2024spp. is a significant zoonotic parasite. The prevalence and infection characteristics of spp. in Bactrian camels in Yili Kazak Autonomous Prefecture have yet to be...
INTRODUCTION
spp. is a significant zoonotic parasite. The prevalence and infection characteristics of spp. in Bactrian camels in Yili Kazak Autonomous Prefecture have yet to be fully understood. Thus, the molecular epidemiology of cryptosporidiosis in camels was investigated in this region.
METHODS
A total of 1,455 fecal samples were collected from 6 counties in three regions (Altay, Tacheng, and Yili) in Yili Prefecture. Nested PCR targeting the small subunit ribosomal RNA ( rRNA) gene was used to identify the species or genotypes of infection in camels. For positive samples, the subtypes were identified using the 60-kDa glycoprotein (gp60) gene.
RESULTS AND DISCUSSION
The overall infection rate was 8.7% (126/1,455), ranging from 5.6% to 11.7% in different regions, and 4.2% to 15.8% in different counties. A significant difference was observed amongst the counties ( < 0.001). Three species were detected, namely (65.1%, 82/126), (34.1%, 43/126), and (0.8%, 1/126). Three subtypes, If-like-A15G2 ( = 29), IIdA15G1 ( = 4), and IIdA19G1( = 1) were detected, with If-like-A15G2 being the most prevalent subtype. Camels aged 3-12 months exhibited the highest infection rate (11.4%, 44/387), with no significant difference among age groups ( > 0.05). was predominant in camels under 3 months, while prevailed in camels over 3 months. There was an extremely significant difference observed among seasons ( < 0.001), summer had the highest infection rates (16.9%, 61/360). This study collected nearly 1,500 samples and, for the first time, investigated spp. infection in camels based on different age groups and seasons. All three species identified were zoonotic, posing a potential threat to human health and requiring close attention.
PubMed: 38915888
DOI: 10.3389/fvets.2024.1411377 -
BioRxiv : the Preprint Server For... Jun 2024Proteostasis, the maintenance of cellular protein balance, is essential for cell viability and is highly conserved across all organisms. Newly synthesized proteins, or...
UNLABELLED
Proteostasis, the maintenance of cellular protein balance, is essential for cell viability and is highly conserved across all organisms. Newly synthesized proteins, or "clients," undergo sequential processing by Hsp40, Hsp70, and Hsp90 chaperones to achieve proper folding and functionality. Despite extensive characterization of post-translational modifications (PTMs) on Hsp70 and Hsp90, the modifications on Hsp40 remain less understood. This study aims to elucidate the role of lysine acetylation on the yeast Hsp40, Ydj1. By mutating acetylation sites on Ydj1's J-domain to either abolish or mimic constitutive acetylation, we observed that preventing acetylation had no noticeable phenotypic impact, whereas acetyl-mimic mutants exhibited various defects indicative of impaired Ydj1 function. Proteomic analysis revealed several Ydj1 interactions affected by J-domain acetylation, notably with proteins involved in translation. Further investigation uncovered a novel role for Ydj1 acetylation in stabilizing ribosomal subunits and ensuring translational fidelity. Our data suggest that acetylation may facilitate the transfer of Ydj1 between Ssa1 and Hsp82. Collectively, this work highlights the critical role of Ydj1 acetylation in proteostasis and translational fidelity.
AUTHOR SUMMARY
Cells require a suite of chaperone and co-chaperone proteins to maintain a healthy balance of functional proteins. A large number of modifications on chaperone and co-chaperone proteins have been identified, but their functional importance has not been fully explored. In this study, we identify acetylation sites on the yeast co-chaperone Ydj1 that impact its interactions with major chaperones and client proteins including those involved in protein synthesis. This work sheds light on how modifications on co-chaperones can also play an important role in the health of the proteome.
PubMed: 38915721
DOI: 10.1101/2024.06.13.598777 -
BioRxiv : the Preprint Server For... Jun 2024Zinc knuckle (ZCCHC) motif-containing proteins are present in unicellular and multicellular eukaryotes and most ZCCHC proteins with known functions participate in the...
Zinc knuckle (ZCCHC) motif-containing proteins are present in unicellular and multicellular eukaryotes and most ZCCHC proteins with known functions participate in the metabolism of various classes of RNA, such as mRNAs, ribosomal RNAs, and microRNAs. The Arabidopsis () genome encodes 69 ZCCHC-containing proteins, but the functions of most remain unclear. One of these proteins is CAX-INTERACTING PROTEIN 4 (CXIP4), which has been classified as a PTHR31437 family member, along with human SREK1-interacting protein 1 (SREK1IP1), which is thought to function in pre-mRNA splicing and RNA methylation. Metazoan SREK1IP1-like and plant CXIP4-like proteins only share a ZCCHC motif, and their functions remain almost entirely unknown. We studied two loss-of-function alleles of Arabidopsis , the first mutations in PTHR31437 family genes described to date: is likely null and shows early lethality, and is hypomorphic and viable, with pleiotropic morphological defects. The mutant exhibited deregulation of defense genes and upregulation of transcription factor encoding genes, some of which might explain its developmental defects. This mutant also exhibited increased intron retention events, and the specific functions of misspliced genes, such as those involved in "gene silencing by DNA methylation" and "mRNA polyadenylation factor" suggest that CXIP4 has additional functions. The CXIP4 protein localizes to the nucleus in a pattern resembling nuclear speckles, which are rich in splicing factors. Therefore, is required for plant survival and proper development, and mRNA maturation.
PubMed: 38915646
DOI: 10.1101/2024.06.06.597795 -
BioRxiv : the Preprint Server For... Jun 2024HflX is known to rescue stalled ribosomes and is implicated in antibiotic resistance in several bacteria. Here we present several high-resolution cryo-EM structures of...
HflX is known to rescue stalled ribosomes and is implicated in antibiotic resistance in several bacteria. Here we present several high-resolution cryo-EM structures of mycobacterial HflX in complex with the ribosome and its 50S subunit, with and without antibiotics. These structures reveal a distinct mechanism for HflX-mediated ribosome splitting and antibiotic resistance in mycobacteria. In addition to dissociating ribosome into two subunits, mycobacterial HflX mediates persistent disordering of multiple 23S rRNA helices to generate an inactive pool of 50S subunits. Mycobacterial HflX also acts as an anti-association factor by binding to pre-dissociated 50S subunits. A mycobacteria-specific insertion in HflX reaches further into the peptidyl transferase center. The position of this insertion overlaps with ribosome-bound macrolides or lincosamide class of antibiotics. The extended conformation of insertion seen in the absence of these antibiotics retracts and adjusts around the bound antibiotics instead of physically displacing them. It therefore likely imparts antibiotic resistance by sequestration of the antibiotic-bound inactive 50S subunits.
PubMed: 38915643
DOI: 10.1101/2024.06.13.598844