{"id":746380,"date":"2026-06-19T03:09:11","date_gmt":"2026-06-19T03:09:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/ca\/746380\/"},"modified":"2026-06-19T03:09:11","modified_gmt":"2026-06-19T03:09:11","slug":"pathogen-forms-biofilms-when-temperatures-drop","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ca\/746380\/","title":{"rendered":"Pathogen forms biofilms when temperatures drop"},"content":{"rendered":"

To increase survival and transmission, the pathogen Pseudomonas aeruginosa forms biofilms, or adherent clumps of cells coated in a slimy matrix, in response to environmental stresses. One environmental stress is a temperature decrease, such as from a human host to room temperature in a hospital, where P. aeruginosa is particularly risky for vulnerable patients.<\/p>\n

\"\"<\/p>\n

Janice Haney Carr, Centers for Disease Control and Prevention, via Wikimedia Commons<\/p>\n

Scanning electron micrograph of Pseudomonas aeruginosa.<\/p>\n

Mechanistically, the secondary messenger cyclic di-guanosine 3\u2019,5\u2019-monophosphate, or c-di-GMP, is increased to promote biofilm formation. While P. aeruginosa expresses many enzymes that regulate c-di-GMP levels, how each enzyme responds to distinct environmental cues remains unclear.<\/p>\n

In a recent study<\/a> published in the Journal of Biological Chemistry, Yanran Li of the University of Hong Kong and a team of researchers in China used a mutant screening library to identify SiaD, a diguanylate cyclase that generates c-di-GMP, as responsible for spurring biofilm formation in P. aeruginosa during temperature downshifts.<\/p>\n

Measured with a membrane-sensitive probe, lipidomics and RNA sequencing, the researchers found that when the temperature shifts from 37\u00b0C to 25\u00b0C, the membrane of P. aeruginosa is perturbed, increasing in fluidity and curvature. The signal transduction module SiaABCD senses and responds to these membrane perturbations by enhancing biofilm formation. Specifically, upon a downshift in temperature, membrane changes activate SiaABCD through inner membrane phosphatase SiaA. SiaA dephosphorylates SiaC, a regulator of c-di-GMP, synthesizing SiaD. SiaD elevates levels of c-di-GMP, leading to the production of matrix-forming polysaccharide Psl and downstream biofilm formation. The authors suggest that barring signaling through SiaA could be a potential strategy to inhibit P. aeruginosa biofilm formation and transmission.<\/p>\n","protected":false},"excerpt":{"rendered":"To increase survival and transmission, the pathogen Pseudomonas aeruginosa forms biofilms, or adherent clumps of cells coated in…\n","protected":false},"author":2,"featured_media":746381,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[49,48,66],"class_list":["post-746380","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ca","tag-canada","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/746380","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=746380"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/746380\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/746381"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=746380"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=746380"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=746380"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}