{"doi":"10.1371/journal.ppat.1008134","title":"The C. elegans CHP1 homolog, pbo-1, functions in innate immunity by regulating the pH of the intestinal lumen","abstract":"Caenorhabditis elegans are soil-dwelling nematodes and models for understanding innate immunity and infection. Previously, we developed a novel fluorescent dye (KR35) that accumulates in the intestine of C. elegans and reports a dynamic wave in intestinal pH associated with the defecation motor program. Here, we use KR35 to show that mutations in the Ca2+-binding protein, PBO-1, abrogate the pH wave, causing the anterior intestine to be constantly acidic. Surprisingly, pbo-1 mutants were also more susceptible to infection by several bacterial pathogens. We could suppress pathogen susceptibility in pbo-1 mutants by treating the animals with pH-buffering bicarbonate, suggesting the pathogen susceptibility is a function of the acidity of the intestinal pH. Furthermore, we use KR35 to show that upon infection by pathogens, the intestinal pH becomes neutral in a wild type, but less so in pbo-1 mutants. C. elegans is known to increase production of reactive oxygen species (ROS), such as H2O2, in response to pathogens, which is an important component of pathogen defense. We show that pbo-1 mutants exhibited decreased H2O2 in response to pathogens, which could also be partially restored in pbo-1 animals treated with bicarbonate. Ultimately, our results support a model whereby PBO-1 functions during infection to facilitate pH changes in the intestine that are protective to the host.","journal":"PLoS Pathogens","year":2020,"id":80869,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":14,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9553,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":418628,"name":"Patrick Lansdon","orcid":"0000-0002-9004-6138","position":1,"is_corresponding":false},{"id":418629,"name":"Aaron M. Bender","orcid":"0000-0003-0432-1648","position":2,"is_corresponding":false},{"id":418630,"name":"Blake R. Peterson","orcid":"0000-0001-8251-3579","position":3,"is_corresponding":false},{"id":367210,"name":"Josephine R. Chandler","orcid":"0000-0001-8944-9813","position":4,"is_corresponding":false},{"id":405148,"name":"Brian D. Ackley","orcid":"0000-0002-1257-2407","position":5,"is_corresponding":false},{"id":418627,"name":"Saida Benomar","orcid":"0000-0003-2395-0343","position":0,"is_corresponding":true}],"reference_count":41,"raw_metadata":null,"created_at":"2026-07-18T21:51:58.988919Z","pmid":"31917826","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}