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The Journal of Biological Chemistry Dec 2023Aggregation behavior provides bacteria protection from harsh environments and threats to survival. Two uncharacterized proteases, LapX and Lap, are important for Vibrio...
Aggregation behavior provides bacteria protection from harsh environments and threats to survival. Two uncharacterized proteases, LapX and Lap, are important for Vibrio cholerae liquid-based aggregation. Here, we determined that LapX is a serine protease with a preference for cleavage after glutamate and glutamine residues in the P1 position, which processes a physiologically based peptide substrate with a catalytic efficiency of 180 ± 80 Ms. The activity with a LapX substrate identified by a multiplex substrate profiling by mass spectrometry screen was 590 ± 20 Ms. Lap shares high sequence identity with an aminopeptidase (termed VpAP) from Vibrio proteolyticus and contains an inhibitory bacterial prepeptidase C-terminal domain that, when eliminated, increases catalytic efficiency on leucine p-nitroanilide nearly four-fold from 5.4 ± 4.1 × 10 Ms to 20.3 ± 4.3 × 10 Ms. We demonstrate that LapX processes Lap to its mature form and thus amplifies Lap activity. The increase is approximately eighteen-fold for full-length Lap (95.7 ± 5.6 × 10 Ms) and six-fold for Lap lacking the prepeptidase C-terminal domain (11.3 ± 1.9 × 10 Ms). In addition, substrate profiling reveals preferences for these two proteases that could inform in vivo function. Furthermore, purified LapX and Lap restore the timing of the V. cholerae aggregation program to a mutant lacking the lapX and lap genes. Both proteases must be present to restore WT timing, and thus they appear to act sequentially: LapX acts on Lap, and Lap acts on the substrate involved in aggregation.
Topics: Bacterial Proteins; Leucyl Aminopeptidase; Peptides; Serine Proteases; Substrate Specificity; Vibrio cholerae; Catalysis
PubMed: 37898401
DOI: 10.1016/j.jbc.2023.105386 -
Frontiers in Cellular and Infection... 2023Gram-negative species are major foodborne pathogens often associated with seafood intake that causes gastroenteritis. On food surfaces, biofilm formation by species...
Gram-negative species are major foodborne pathogens often associated with seafood intake that causes gastroenteritis. On food surfaces, biofilm formation by species enhances the resistance of bacteria to disinfectants and antimicrobial agents. Hence, an efficient antibacterial and antibiofilm approach is urgently required. This study examined the antibacterial and antivirulence effects of chromones and their 26 derivatives against and . 6-Bromo-3-formylchromone (6B3FC) and 6-chloro-3-formylchromone (6C3FC) were active antibacterial and antibiofilm compounds. Both 6B3FC and 6C3FC exhibited minimum inhibitory concentrations (MICs) of 20 µg/mL for planktonic cell growth and dose-dependently inhibited biofilm formation. Additionally, they decreased swimming motility, protease activity, fimbrial agglutination, hydrophobicity, and indole production at 20 µg/mL which impaired the growth of the bacteria. Furthermore, the active compounds could completely inhibit the slimy substances and microbial cells on the surface of the squid and shrimp. The most active compound 6B3FC inhibited the gene expression associated in quorum sensing and biofilm formation (, ), pathogenicity (), and membrane integrity () in . However, toxicity profiling using seed germination and models suggests that 6C3FC may have moderate effect at 50 µg/mL while 6B3FC was toxic to the nematodes 20-100 µg/mL. These findings suggest chromone analogs, particularly two halogenated formylchromones (6B3FC and 6C3FC), were effective antimicrobial and antibiofilm agents against in the food and pharmaceutical sectors.
Topics: Animals; Vibrio parahaemolyticus; Anti-Infective Agents; Anti-Bacterial Agents; Caenorhabditis elegans; Biofilms
PubMed: 37662002
DOI: 10.3389/fcimb.2023.1234668 -
Emerging Infectious Diseases Aug 2023Since February 2022, Malawi has experienced a cholera outbreak of >54,000 cases. We investigated 6 cases in South Africa and found that isolates linked to the outbreak...
Since February 2022, Malawi has experienced a cholera outbreak of >54,000 cases. We investigated 6 cases in South Africa and found that isolates linked to the outbreak were Vibrio cholerae O1 serotype Ogawa from seventh pandemic El Tor sublineage AFR15, indicating a new introduction of cholera into Africa from south Asia.
Topics: Humans; Cholera; South Africa; Vibrio cholerae O1; Asia, Southern; Malawi; Disease Outbreaks
PubMed: 37352549
DOI: 10.3201/eid2908.230750 -
Frontiers in Immunology 2023Cholera, a persistent global public health concern, continues to cause outbreaks in approximately 30 countries and territories this year. The imperative to safeguard... (Review)
Review
Cholera, a persistent global public health concern, continues to cause outbreaks in approximately 30 countries and territories this year. The imperative to safeguard water sources and food from Vibrio cholerae, the causative pathogen, remains urgent. The bacterium is mainly disseminated via ingestion of contaminated water or food. Despite the plate method's gold standard status for detection, its time-consuming nature, taking several days to provide results, remains a challenge. The emergence of novel virulence serotypes raises public health concerns, potentially compromising existing detection methods. Hence, exploiting Vibrio cholerae toxin testing holds promise due to its inherent stability. Immunobiosensors, leveraging antibody specificity and sensitivity, present formidable tools for detecting diverse small molecules, encompassing drugs, hormones, toxins, and environmental pollutants. This review explores cholera toxin detection, highlighting phage display-based nano immunosensors' potential. Engineered bacteriophages exhibit exceptional cholera toxin affinity, through specific antibody fragments or mimotopes, enabling precise quantification. This innovative approach promises to reshape cholera toxin detection, offering an alternative to animal-derived methods. Harnessing engineered bacteriophages aligns with ethical detection and emphasizes sensitivity and accuracy, a pivotal stride in the evolution of detection strategies. This review primarily introduces recent advancements in phage display-based nano immunosensors for cholera toxin, encompassing technical aspects, current challenges, and future prospects.
Topics: Humans; Cholera Toxin; Vibrio cholerae; Cholera; Bacteriophages; Water
PubMed: 37781379
DOI: 10.3389/fimmu.2023.1224397 -
Nature Communications Mar 2024Matrix-encapsulated communities of bacteria, called biofilms, are ubiquitous in the environment and are notoriously difficult to eliminate in clinical and industrial...
Matrix-encapsulated communities of bacteria, called biofilms, are ubiquitous in the environment and are notoriously difficult to eliminate in clinical and industrial settings. Biofilm formation likely evolved as a mechanism to protect resident cells from environmental challenges, yet how bacteria undergo threat assessment to inform biofilm development remains unclear. Here we find that population-level cell lysis events induce the formation of biofilms by surviving Vibrio cholerae cells. Survivors detect threats by sensing a cellular component released through cell lysis, which we identify as norspermidine. Lysis sensing occurs via the MbaA receptor with genus-level specificity, and responsive biofilm cells are shielded from phage infection and attacks from other bacteria. Thus, our work uncovers a connection between bacterial lysis and biofilm formation that may be broadly conserved among microorganisms.
Topics: Bacteriophages; Biofilms; Cell Aggregation; Cell Death; Vibrio cholerae
PubMed: 38443393
DOI: 10.1038/s41467-024-46399-1 -
Science (New York, N.Y.) Apr 2024Despite an increasingly detailed picture of the molecular mechanisms of bacteriophage (phage)-bacterial interactions, we lack an understanding of how these interactions...
Despite an increasingly detailed picture of the molecular mechanisms of bacteriophage (phage)-bacterial interactions, we lack an understanding of how these interactions evolve and impact disease within patients. In this work, we report a year-long, nationwide study of diarrheal disease patients in Bangladesh. Among cholera patients, we quantified (prey) and its virulent phages (predators) using metagenomics and quantitative polymerase chain reaction while accounting for antibiotic exposure using quantitative mass spectrometry. Virulent phage (ICP1) and antibiotics suppressed to varying degrees and were inversely associated with severe dehydration depending on resistance mechanisms. In the absence of antiphage defenses, predation was "effective," with a high predator:prey ratio that correlated with increased genetic diversity among the prey. In the presence of antiphage defenses, predation was "ineffective," with a lower predator:prey ratio that correlated with increased genetic diversity among the predators. Phage-bacteria coevolution within patients should therefore be considered in the deployment of phage-based therapies and diagnostics.
Topics: Cholera; Vibrio cholerae; Bacteriophages; Humans; Genetic Variation; Bangladesh; Anti-Bacterial Agents; Severity of Illness Index; Adult; Metagenomics
PubMed: 38669570
DOI: 10.1126/science.adj3166 -
Developmental and Comparative Immunology Nov 2023Lysin motif (LysM) is a functional domain that can bind to peptidoglycans, chitin and their derivatives. The LysM-containing proteins participate in multiple biological...
Lysin motif (LysM) is a functional domain that can bind to peptidoglycans, chitin and their derivatives. The LysM-containing proteins participate in multiple biological processes, such as the hydrolysis of bacterial cell walls and the perception of PAMPs in plants and high animals. In the present study, two genes encoding LysM-containing proteins, designated as LvLysM1 and LvLysM2, were identified in the Pacific white shrimp, Litopenaeus vannamei, and their functions during Vibrio infection were analyzed. The open-reading frame (ORF) of LvLysM1 was 795 bp, only encoding a LysM domain at the N-terminal region. The ORF of LvLysM2 was 834 bp, encoding a LysM domain at the central region and a transmembrane region at the C-terminal region. Both LvLysM1 and LvLysM2 were widely transcribed in all tested shrimp tissues. Enzyme-linked immunosorbent assay (ELISA) showed that the recombinant protein of LvLysM2 could bind to different bacterial polysaccharides, while LvLysM1 showed no direct binding activity. The transcripts of LvLysMs in gills increased significantly after infection with Vibrio parahaemolyticus. When LvLysM1 or LvLysM2 was knocked down by dsRNA, the mortality of shrimp was significantly increased after infection with Vibrio parahaemolyticus. Interestingly, some SNPs existed in these two genes were apparently correlated with the Vp resistance of shrimp. These results suggested that LvLysM1 and LvLysM2 might contribute to the disease resistance of shrimp. The data provide new knowledge about the function of LysM-containing proteins in shrimp and potential genetic markers for disease resistance breeding.
Topics: Animals; Vibrio parahaemolyticus; Disease Resistance; Arthropod Proteins; Immunity, Innate; Vibrio Infections; Protein Domains; Penaeidae
PubMed: 37536402
DOI: 10.1016/j.dci.2023.104900 -
Nature Microbiology Oct 2023Since 2016, Yemen has been experiencing the largest cholera outbreak in modern history. Multidrug resistance (MDR) emerged among Vibrio cholerae isolates from cholera...
Since 2016, Yemen has been experiencing the largest cholera outbreak in modern history. Multidrug resistance (MDR) emerged among Vibrio cholerae isolates from cholera patients in 2018. Here, to characterize circulating genotypes, we analysed 260 isolates sampled in Yemen between 2018 and 2019. Eighty-four percent of V. cholerae isolates were serogroup O1 belonging to the seventh pandemic El Tor (7PET) lineage, sub-lineage T13, whereas 16% were non-toxigenic, from divergent non-7PET lineages. Treatment of severe cholera with macrolides between 2016 and 2019 coincided with the emergence and dominance of T13 subclones carrying an incompatibility type C (IncC) plasmid harbouring an MDR pseudo-compound transposon. MDR plasmid detection also in endemic non-7PET V. cholerae lineages suggested genetic exchange with 7PET epidemic strains. Stable co-occurrence of the IncC plasmid with the SXT family of integrative and conjugative element in the 7PET background has major implications for cholera control, highlighting the importance of genomic epidemiological surveillance to limit MDR spread.
Topics: Humans; Cholera; Vibrio cholerae O1; Yemen; Plasmids; Genomics
PubMed: 37770747
DOI: 10.1038/s41564-023-01472-1 -
Cell Reports Oct 2023Cyclic di-guanosine monophosphate (c-di-GMP) is a unique bacterial second messenger but is hijacked by host cells during bacterial infection as a pathogen-associated...
Cyclic di-guanosine monophosphate (c-di-GMP) is a unique bacterial second messenger but is hijacked by host cells during bacterial infection as a pathogen-associated molecular pattern (PAMP) to trigger STING-dependent immune responses. Here, we show that upon infection, VopY, an effector of Vibrio parahaemolyticus, is injected into host cells by type III secretion system 2 (T3SS2), a secretion system unique to its pathogenic strains and indispensable for enterotoxicity. VopY is an EAL-domain-containing phosphodiesterase and is capable of hydrolyzing c-di-GMP. VopY expression in host cells prevents the activation of STING and STING-dependent downstream signaling triggered by c-di-GMP and, consequently, suppresses type I interferon immune responses. The presence of VopY in V. parahaemolyticus enables it to cause both T3SS2-dependent enterotoxicity and cytotoxicity. These findings uncover the destruction of self-derived PAMPs by injecting specific effectors to suppress PAMP-triggered immune responses as a unique strategy for bacterial pathogens to subvert immunity and cause disease.
Topics: Vibrio parahaemolyticus; Virulence; Innate Immunity Recognition; Type III Secretion Systems; Bacterial Proteins
PubMed: 37847589
DOI: 10.1016/j.celrep.2023.113261 -
PLoS Genetics Jul 2023Quorum sensing (QS) is a chemical communication process that bacteria use to track population density and orchestrate collective behaviors. QS relies on the production,...
Quorum sensing (QS) is a chemical communication process that bacteria use to track population density and orchestrate collective behaviors. QS relies on the production, accumulation, and group-wide detection of extracellular signal molecules called autoinducers. Vibriophage 882 (phage VP882), a bacterial virus, encodes a homolog of the Vibrio QS receptor-transcription factor, called VqmA, that monitors the Vibrio QS autoinducer DPO. Phage VqmA binds DPO at high host-cell density and activates transcription of the phage gene qtip. Qtip, an antirepressor, launches the phage lysis program. Phage-encoded VqmA when bound to DPO also manipulates host QS by activating transcription of the host gene vqmR. VqmR is a small RNA that controls downstream QS target genes. Here, we sequence Vibrio parahaemolyticus strain O3:K6 882, the strain from which phage VP882 was initially isolated. The chromosomal region normally encoding vqmR and vqmA harbors a deletion encompassing vqmR and a portion of the vqmA promoter, inactivating that QS system. We discover that V. parahaemolyticus strain O3:K6 882 is also defective in its other QS systems, due to a mutation in luxO, encoding the central QS transcriptional regulator LuxO. Both the vqmR-vqmA and luxO mutations lock V. parahaemolyticus strain O3:K6 882 into the low-cell density QS state. Reparation of the QS defects in V. parahaemolyticus strain O3:K6 882 promotes activation of phage VP882 lytic gene expression and LuxO is primarily responsible for this effect. Phage VP882-infected QS-competent V. parahaemolyticus strain O3:K6 882 cells lyse more rapidly and produce more viral particles than the QS-deficient parent strain. We propose that, in V. parahaemolyticus strain O3:K6 882, constitutive maintenance of the low-cell density QS state suppresses the launch of the phage VP882 lytic cascade, thereby protecting the bacterial host from phage-mediated lysis.
Topics: Quorum Sensing; Bacteriophages; Vibrio parahaemolyticus; Vibrio cholerae; Transcription Factors
PubMed: 37523407
DOI: 10.1371/journal.pgen.1010809