{"id":36633,"date":"2025-07-10T07:15:38","date_gmt":"2025-07-10T05:15:38","guid":{"rendered":"https:\/\/www.co2news.sk\/?p=36633"},"modified":"2025-07-10T07:17:26","modified_gmt":"2025-07-10T05:17:26","slug":"sequestration-of-co2-and-elimination-of-harmful-ammonia","status":"publish","type":"post","link":"https:\/\/www.co2news.sk\/en\/2025\/07\/10\/sequestration-of-co2-and-elimination-of-harmful-ammonia\/","title":{"rendered":"CO2 sequestration and elimination of harmful ammonia"},"content":{"rendered":"<p><em>Bacillus megaterium<\/em> is a unique microorganism that possesses <strong>dual enzymatic capabilities<\/strong> for the precipitation of calcium carbonate (CaCO\u2083), through enzymes<!--more--> <strong>urease<\/strong> a <strong>carbonic anhydrase (CA)<\/strong>Which of these metabolic pathways <em>B. megaterium<\/em> prefers is significantly influenced by the concentration of CO\u2082 in its environment, which has key implications for the biosynthesis of materials and carbon sequestration.<\/p>\n<p>For <strong>atmospheric CO\u2082 levels<\/strong> (and in the presence of urea and CaCl\u2082), <em>B. megaterium<\/em> activates <strong>ureolytic pathway<\/strong>. This process involves the hydrolysis of urea (CH\u2084N\u2082O) to carbonate (CO\u2083\u00b2-) and ammonium ion (NH\u2084+). Subsequently, Ca\u00b2+ combines with carbonate to form CaCO\u2083, with calcite being identified as the precipitated polymorph. However, it is important to note that ammonium ion is an undesirable by-product that requires additional wastewater treatment.<\/p>\n<p>The situation changes when <strong>elevated CO\u2082 levels<\/strong>, specifically at levels <strong>more than 470 times higher than atmospheric levels<\/strong>In such conditions <em>B. megaterium<\/em> activates the enzyme <strong>carbonic anhydrase (CA)<\/strong>. Carbonic anhydrase catalyzes the hydration of the CO\u2082 molecule to bicarbonate (HCO\u2083-). The bicarbonate ions are then converted to carbonate ions (CO\u2083\u00b2-), which combine with free Ca\u00b2- cations to form CaCO\u2083.<\/p>\n<p>Key experiments using C\u00b9\u00b3-labeled urea confirmed this change in preference: at elevated CO\u2082 concentrations, up to <strong>94 %<\/strong> of precipitated CaCO\u2083 formed by CO\u2082 mineralization, while only approx. <strong>6 %<\/strong> came from ureolysis. This means that <em>B. megaterium<\/em> at high CO\u2082 concentrations, it primarily uses its carbonic anhydrase pathway for CaCO\u2083 synthesis.<\/p>\n<p>The advantage of the CA-mediated path is obvious: it allows <strong>direct binding of atmospheric CO\u2082<\/strong> into CaCO\u2083 and at the same time <strong>minimizes the formation of potentially dangerous metabolic byproducts<\/strong>, such as ammonia, which are associated with the ureolytic pathway. This understanding of the selective activation of metabolic pathways opens up promising possibilities for future strategies for microbially induced carbon dioxide sequestration (MICO2S) and the development of sustainable building materials. <em><strong>Spring<\/strong><\/em><\/p>\n<hr \/>\n<p>The study was <span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"https:\/\/www.nature.com\/articles\/s41598-025-07323-9\" target=\"_blank\" rel=\"noopener\">published<\/a><\/span>\u00a0in\u00a0<i>Scientific Reports magazine<\/i>\u00a0.<\/p>","protected":false},"excerpt":{"rendered":"<p>Bacillus megaterium is a unique microorganism that possesses dual enzymatic capabilities for the precipitation of calcium carbonate (CaCO\u2083) through enzymes<\/p>","protected":false},"author":7,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-36633","post","type-post","status-publish","format-standard","hentry","category-znizovanie_co2_cdr_ccs_ccu_dac"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/posts\/36633","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/comments?post=36633"}],"version-history":[{"count":0,"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/posts\/36633\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/media?parent=36633"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/categories?post=36633"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.co2news.sk\/en\/wp-json\/wp\/v2\/tags?post=36633"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}