{"id":2670,"date":"2025-12-11T12:02:08","date_gmt":"2025-12-11T17:02:08","guid":{"rendered":"https:\/\/lifetein.com\/blog\/?p=2670"},"modified":"2025-12-11T12:02:09","modified_gmt":"2025-12-11T17:02:09","slug":"unusual-amino-acids-propargylglycine-pra","status":"publish","type":"post","link":"https:\/\/www.lifetein.com\/blog\/unusual-amino-acids-propargylglycine-pra\/","title":{"rendered":"Unusual Amino Acids: Propargylglycine (Pra)"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" width=\"640\" height=\"334\" src=\"https:\/\/lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine1.webp\" alt=\"Propargylglycine (Pra)\" class=\"wp-image-2683\" srcset=\"https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine1.webp 640w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine1-300x157.webp 300w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine1-500x261.webp 500w\" sizes=\"(max-width: 640px) 100vw, 640px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Propargylglycine (Pra)<\/strong>&nbsp;is a prominent&nbsp;<strong>unnatural amino acid<\/strong>&nbsp;that has become an indispensable tool in chemical biology and peptide engineering. Classified as a&nbsp;<strong>non-proteinogenic<\/strong>&nbsp;building block, it is not incorporated into proteins by the ribosomal machinery but is instead used synthetically to bestow novel chemical and biological properties upon peptides<a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC9044140\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. Its defining feature is a&nbsp;<strong>terminal alkyne moiety<\/strong>&nbsp;(-C\u2261CH) appended to the side chain of glycine, creating a versatile handle for&nbsp;<strong>bioorthogonal chemistry<\/strong><a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. This simple yet powerful modification enables Pra to serve dual roles: as a potent, mechanism-based inhibitor of key enzymes in sulfur metabolism and as a unique chemical tag for precise, site-specific modification of biomolecules<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n<h4 class=\"wp-block-heading\" id=\"key-takeaways\">Key Takeaways<\/h4>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Pra features a terminal alkyne side chain<\/strong>, making it a cornerstone for&nbsp;<strong>Cu-catalyzed azide-alkyne cycloaddition (CuAAC) &#8220;click chemistry&#8221;<\/strong>&nbsp;in peptide and protein labeling<a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/li>\n\n\n\n<li>It acts as a&nbsp;<strong>potent and irreversible inhibitor<\/strong>&nbsp;of the enzyme&nbsp;<strong>cystathionine \u03b3-lyase (CSE)<\/strong>, a key player in the endogenous production of hydrogen sulfide (H\u2082S)<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/li>\n\n\n\n<li>As an&nbsp;<strong>unnatural amino acid<\/strong>, Pra is used to expand the functional repertoire of synthetic peptides, allowing for the installation of probes, tags, and stabilizers to enhance their utility in research and drug discovery<a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC9044140\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC11901032\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\" id=\"fundamentals-of-propargylglycine\">Fundamentals of Propargylglycine<\/h2>\n\n<h4 class=\"wp-block-heading\" id=\"chemical-structure-and-properties-of-pra\">Chemical Structure and Properties of Pra<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Propargylglycine, with the molecular formula C\u2085H\u2087NO\u2082 and a molecular weight of 113.1 g\/mol, is the simplest&nbsp;<strong>alkyne-bearing amino acid<\/strong><a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. Its IUPAC name is 2-amino-4-pentynoic acid. Structurally, it is an analog of the natural amino acid&nbsp;<strong>glycine<\/strong>, where one hydrogen on the alpha-carbon is replaced by a&nbsp;<strong>propargyl group<\/strong>&nbsp;(-CH\u2082-C\u2261CH). This L-configuration amino acid is typically supplied as a white to light-yellow crystalline powder<a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. The presence of the&nbsp;<strong>terminal alkyne<\/strong>&nbsp;is central to all its applications, providing a site of unique chemical reactivity absent from the canonical 20 amino acids.<\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"the-dual-roles-of-propargylglycine-pra\">The Dual Roles of Propargylglycine (Pra)<\/h2>\n\n<h4 class=\"wp-block-heading\" id=\"propargylglycine-pra-as-a-potent-biochemical-inhibitor\">Propargylglycine (Pra) as A Potent Biochemical Inhibitor<\/h4>\n\n\n<p class=\"wp-block-paragraph\">One of the most well-established applications of Pra, particularly its D,L-form, is as a&nbsp;<strong>mechanism-based enzyme inhibitor<\/strong>. It is a&nbsp;<strong>specific and potent inhibitor of cystathionine \u03b3-lyase (CSE)<\/strong>, with a reported half-maximal inhibitory concentration (IC\u2085\u2080) of approximately 40 \u00b5M<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. CSE is a pivotal enzyme in the transsulfuration pathway, responsible for the endogenous production of the gaseous signaling molecule&nbsp;<strong>hydrogen sulfide (H\u2082S)<\/strong>. By irreversibly inhibiting CSE, Pra becomes a crucial pharmacological tool for studying the complex physiological and pathological roles of H\u2082S in systems ranging from cardiovascular function and neuroscience to inflammation and cancer metabolism<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.lifetein.com\/peptide_synthesis_services.html?_gl=1*15bjc7l*_gcl_aw*R0NMLjE3NTIyNTk1NTEuQ2p3S0NBanc3TUxEQmhBdUVpd0FJZVhHSVpVMXFSOXh4MzJEX3d6U2NYYUx2aWhzLWYzMU1FZ3VOSDRhcW41NUJtZmM1RnN3MkdVR0tSb0NCS01RQXZEX0J3RQ..*_gcl_au*NzY2NTIxODguMTc1MTUyMjM4MQ..&amp;_ga=2.129734156.1835841867.1753856001-90406248.1735925224\" target=\"_blank\" rel=\"noreferrer noopener\">Find out more about peptide synthesis here<\/a>.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"a-versatile-handle-for-bioorthogonal-chemistry\">A Versatile Handle for Bioorthogonal Chemistry<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Beyond its inhibitory function, the true power of Pra in synthetic chemistry lies in its&nbsp;<strong>alkyne functional group<\/strong>. This group participates efficiently in the&nbsp;<strong>Cu-catalyzed azide-alkyne cycloaddition (CuAAC)<\/strong>, a premier example of &#8220;click chemistry&#8221;<a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. This reaction is highly selective, proceeds rapidly under mild conditions, and is virtually inert to other biological functional groups, making it&nbsp;<strong>bioorthogonal<\/strong>. Consequently, peptides or proteins incorporating Pra can be selectively and covalently &#8220;tagged&#8221; with any molecule carrying an azide group, such as fluorescent dyes, biotin, polymers, or other peptides.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"1024\" height=\"222\" src=\"https:\/\/lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-1024x222.webp\" alt=\"Propargylglycine (Pra)\" class=\"wp-image-2684\" srcset=\"https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-1024x222.webp 1024w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-300x65.webp 300w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-768x166.webp 768w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-1536x333.webp 1536w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2-500x108.webp 500w, https:\/\/www.lifetein.com\/blog\/wp-content\/uploads\/2025\/12\/Propargylglycine2.webp 1920w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Propargylglycine utilized with Click Chemistry<\/figcaption><\/figure>\n\n\n<h2 class=\"wp-block-heading\" id=\"propargylglycine-pra-in-peptide-science-and-engineering\">Propargylglycine (Pra) in Peptide Science and Engineering<\/h2>\n\n<h4 class=\"wp-block-heading\" id=\"pra-incorporation-into-synthetic-peptides\">Pra Incorporation into Synthetic Peptides<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Pra is routinely incorporated into peptides using standard&nbsp;<strong>solid-phase peptide synthesis (SPPS)<\/strong>&nbsp;methodologies. Specialized peptide synthesis service providers can include Pra and other&nbsp;<strong>unnatural amino acids<\/strong>&nbsp;into custom sequences to meet specific research needs<a href=\"https:\/\/www.peptide.com\/custom-peptides\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. The incorporation is straightforward, treating Pra as a unique building block during the sequential assembly of the peptide chain. This allows researchers to precisely control the location of the reactive alkyne handle within the peptide structure.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"enabling-advanced-peptide-ligand-design\">Enabling Advanced Peptide Ligand Design<\/h4>\n\n\n<p class=\"wp-block-paragraph\">A sophisticated application of Pra is in the rational design of high-affinity peptide ligands. A novel strategy involves the&nbsp;<strong>single-point substitution of a lysine residue with Pra<\/strong>&nbsp;within a peptide sequence<a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. Following synthesis, the alkyne of Pra is used to attach an&nbsp;<strong>aminophilic salicylaldehyde tag<\/strong>&nbsp;via CuAAC. This tag can then form a&nbsp;<strong>reversible covalent bond<\/strong>&nbsp;with a lysine residue on the target protein&#8217;s surface. This approach has been successfully demonstrated to enhance the affinity of a peptide for its target, NEMO, showcasing a powerful method to convert standard peptides into potent,&nbsp;<strong>reversible-covalent binders<\/strong><a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"pra-advantages-in-peptide-therapeutic-optimization\">Pra Advantages in Peptide Therapeutic Optimization<\/h4>\n\n\n<p class=\"wp-block-paragraph\">The use of&nbsp;<strong>unnatural amino acids<\/strong>&nbsp;like Pra aligns with broader strategies in peptide drug discovery to overcome inherent limitations of natural peptides, such as poor metabolic stability and low membrane permeability<a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC11901032\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. Introducing Pra can modulate a peptide&#8217;s&nbsp;<strong>physicochemical properties<\/strong>, alter its conformation, and provide a direct avenue for conjugation to half-life extending polymers (like PEG) or drug carriers. Furthermore, the alkyne handle can be used to install environment-sensitive fluorophores for imaging or tracking, as noted in studies with cystine knot peptides<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.lifetein.com\/Rush-Peptide-Synthesis-Service.html?_gl=1*15bjc7l*_gcl_aw*R0NMLjE3NTIyNTk1NTEuQ2p3S0NBanc3TUxEQmhBdUVpd0FJZVhHSVpVMXFSOXh4MzJEX3d6U2NYYUx2aWhzLWYzMU1FZ3VOSDRhcW41NUJtZmM1RnN3MkdVR0tSb0NCS01RQXZEX0J3RQ..*_gcl_au*NzY2NTIxODguMTc1MTUyMjM4MQ..&amp;_ga=2.129734156.1835841867.1753856001-90406248.1735925224\" target=\"_blank\" rel=\"noreferrer noopener\">Find out about high-speed RUSH synthesis.<\/a><\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"frequently-asked-questions-faq\">Frequently Asked Questions (FAQ)<\/h2>\n\n<h4 class=\"wp-block-heading\" id=\"what-makes-propargylglycine-an-unusual-or-unnatural-amino-acid\">What makes Propargylglycine an &#8220;unusual&#8221; or &#8220;unnatural&#8221; amino acid?<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Propargylglycine is classified as&nbsp;<strong>unnatural<\/strong>&nbsp;or&nbsp;<strong>non-proteinogenic<\/strong>&nbsp;because its structure, featuring an alkyne side chain, does not exist among the 20 standard amino acids encoded by DNA and used in natural ribosomal protein synthesis<a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC9044140\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. It is a product of synthetic chemistry designed to provide functionalities not available in nature.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"is-pras-primary-use-as-an-inhibitor-or-a-chemical-handle\">Is Pra&#8217;s primary use as an inhibitor or a chemical handle?<\/h4>\n\n\n<p class=\"wp-block-paragraph\">It serves both critical functions, and the primary use depends on the research context. In physiological and pharmacological studies, its&nbsp;<strong>role as a CSE inhibitor<\/strong>&nbsp;to probe H\u2082S biology is paramount<a href=\"https:\/\/www.sciencedirect.com\/topics\/medicine-and-dentistry\/propargylglycine\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. In chemical biology, biotechnology, and drug discovery, its&nbsp;<strong>utility as a bioorthogonal click chemistry handle<\/strong>&nbsp;for labeling and conjugating biomolecules is its key asset<a href=\"https:\/\/www.linkedin.com\/posts\/alberto-dal-corso-33a2b046_lysines-are-highly-abundant-on-protein-surfaces-activity-7401300773613080576-nBo4\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"how-is-pra-incorporated-into-peptides\">How is Pra incorporated into peptides?<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Pra is incorporated synthetically. The most common method is&nbsp;<strong>solid-phase peptide synthesis<\/strong>, where it is used as a protected amino acid building block and coupled in sequence like any standard amino acid<a href=\"https:\/\/www.peptide.com\/custom-peptides\/\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>. For producing more complex proteins, advanced techniques like genetic code expansion in live cells can be used to incorporate Pra site-specifically.<\/p>\n\n\n<h4 class=\"wp-block-heading\" id=\"can-pra-be-purchased-for-research\">Can Pra be purchased for research?<\/h4>\n\n\n<p class=\"wp-block-paragraph\">Yes,&nbsp;<strong>L-Propargylglycine<\/strong>&nbsp;is commercially available from fine chemical and biochemical suppliers. It is typically sold as a high-purity (e.g., \u226598%) powder for research use<a href=\"https:\/\/www.chemimpex.com\/products\/02726?srsltid=AfmBOopNpG-Q4kSQow-vqIKAxC1RAcMDUm4NDIaR1a1nPKumB4fIwwNV\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Adhikari, A., Bhattarai, B. R., Aryal, A., Thapa, N., KC, P., Adhikari, A., Maharjan, S., Chanda, P. B., Regmi, B. P., &amp; Parajuli, N. (2021). Reprogramming natural proteins using unnatural amino acids. RSC Advances, 11(60), 38126\u201338145. https:\/\/doi.org\/10.1039\/d1ra07028b<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Sharma, K. K., Sharma, K., Rao, K., Sharma, A., Rathod, G. K., Aaghaz, S., Sehra, N., Parmar, R., VanVeller, B., &amp; Jain, R. (2024). Unnatural Amino Acids: Strategies, Designs, and Applications in Medicinal Chemistry and Drug Discovery. Journal of Medicinal Chemistry, 67(22), 19932\u201319965. https:\/\/doi.org\/10.1021\/acs.jmedchem.4c00110<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Propargylglycine (Pra)&nbsp;is a prominent&nbsp;unnatural amino acid&nbsp;that has become an indispensable tool in chemical biology and peptide engineering. Classified as a&nbsp;non-proteinogenic&nbsp;building block, it is not incorporated into proteins by the ribosomal machinery but is instead used synthetically to bestow novel chemical &hellip; <a href=\"https:\/\/www.lifetein.com\/blog\/unusual-amino-acids-propargylglycine-pra\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":6,"featured_media":2683,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-2670","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-peptide_synthesis"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/posts\/2670","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/comments?post=2670"}],"version-history":[{"count":5,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/posts\/2670\/revisions"}],"predecessor-version":[{"id":2689,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/posts\/2670\/revisions\/2689"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/media\/2683"}],"wp:attachment":[{"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/media?parent=2670"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/categories?post=2670"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lifetein.com\/blog\/wp-json\/wp\/v2\/tags?post=2670"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}