{"response":{"status":"ok","message_type":"publication"},"id":1702,"citation":"Kumar et al., 2019, The FEBS Journal","doi":"10.1111/febs.14921","url":"https://api.seqco.de/v1/publications/1702.json","link_ext":"https://doi.org/10.1111/febs.14921","title":"Crystal structures of a putative periplasmic cystine‐binding protein from \u003ci\u003eCandidatus\u003c/i\u003e Liberibacter asiaticus: insights into an adapted mechanism of ligand binding","journal":"The FEBS Journal","journal_loc":"286 (17)","journal_date":"2019-09-01","pub_type":"journal-article","abstract":"\u003cjats:p\u003eThe amino acid‐binding receptors, a component of \u003cjats:styled-content style=\"fixed-case\"\u003eABC\u003c/jats:styled-content\u003e transporters, have evolved to cater to different specificities and functions. Of particular interest are cystine‐binding receptors, which have shown broad specificity. In the present study, a putative periplasmic cystine‐binding protein from \u003cjats:italic\u003eCandidatus\u003c/jats:italic\u003e Liberibacter asiaticus (\u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA) was characterized. Analysis of the \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA sequence and crystal structures in the ligand‐bound state revealed novel features of \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA in comparison to related proteins. One of the unique features found in \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA structure was the positioning of the C‐terminal extended loop of one chain very close to the substrate‐binding site of the adjacent monomer in the asymmetric unit. The presence of a disulphide bond, unique to \u003cjats:italic\u003eCandidatus\u003c/jats:italic\u003e Liberibacter family, holds the C‐terminal extended loop in position. Analysis of the substrate‐binding pocket of \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA suggested a broad specificity and a completely different orientation of the bound substrates in comparison to related protein structures. The open conformation for one of the two chains of the asymmetric unit in the Arg‐bound structure revealed a limited open state (18.4°) for \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA as compared to open state of other related proteins (~ 60°). The strong interaction between Asp126 on helix‐α5 of small domain and Arg82 (bigger domain) restricts the degree of opening in ligand‐free open state. The dissociation constant of 1.26 μ\u003cjats:sc\u003em\u003c/jats:sc\u003e by \u003cjats:styled-content style=\"fixed-case\"\u003eSPR\u003c/jats:styled-content\u003e and 3.7 μ\u003cjats:sc\u003em\u003c/jats:sc\u003e by \u003cjats:styled-content style=\"fixed-case\"\u003eMST\u003c/jats:styled-content\u003e exhibited low affinity for the cystine. This is the first structural characterization of an \u003cjats:sc\u003el\u003c/jats:sc\u003e‐cystine \u003cjats:styled-content style=\"fixed-case\"\u003eABC\u003c/jats:styled-content\u003e transporter from plant pathogen and our results suggest that \u003cjats:styled-content style=\"fixed-case\"\u003eCL\u003c/jats:styled-content\u003easTcyA may have evolved to cater to its specific needs for its survival in the host.\u003c/jats:p\u003e","long_citation_html":"Kumar et al. (2019). Crystal structures of a putative periplasmic cystine‐binding protein from \u003ci\u003eCandidatus\u003c/i\u003e Liberibacter asiaticus: insights into an adapted mechanism of ligand binding. \n\u003ci\u003eThe FEBS Journal\u003c/i\u003e. \u003ca href=\"https://doi.org/10.1111/febs.14921\" target=\"_blank\"\u003eDOI:10.1111/febs.14921\u003c/a\u003e\n","created_at":"2019-05-27T00:54:06.762Z","updated_at":"2025-11-06T13:43:44.113Z","authors":[{"id":5752,"given":"Pranav","family":"Kumar","created_at":"2019-04-15T19:29:40.884Z","updated_at":"2019-04-15T19:29:40.884Z","url":"https://api.seqco.de/v1/authors/5752.json"},{"id":6532,"given":"Pooja","family":"Kesari","created_at":"2019-05-27T00:54:06.818Z","updated_at":"2019-05-27T00:54:06.818Z","url":"https://api.seqco.de/v1/authors/6532.json"},{"id":5751,"given":"Sunil","family":"Kokane","created_at":"2019-04-15T19:29:40.870Z","updated_at":"2019-04-15T19:29:40.870Z","url":"https://api.seqco.de/v1/authors/5751.json"},{"id":2763,"given":"Dilip Kumar","family":"Ghosh","created_at":"2019-04-15T18:47:31.664Z","updated_at":"2019-04-15T18:47:31.664Z","url":"https://api.seqco.de/v1/authors/2763.json"},{"id":554,"given":"Pravindra","family":"Kumar","created_at":"2019-04-15T18:46:10.713Z","updated_at":"2019-04-15T18:46:10.713Z","url":"https://api.seqco.de/v1/authors/554.json"},{"id":2764,"given":"Ashwani Kumar","family":"Sharma","created_at":"2019-04-15T18:47:31.681Z","updated_at":"2019-04-15T18:47:31.681Z","url":"https://api.seqco.de/v1/authors/2764.json"}],"names":[{"id":1,"name":"Candidatus Liberibacter asiaticus","url":"https://api.seqco.de/v1/names/1.json","uri":"https://seqco.de/i:1"}],"subjects":[{"id":35,"name":"Biochemistry","url":"https://api.seqco.de/v1/subjects/35.json"},{"id":30,"name":"Cell Biology","url":"https://api.seqco.de/v1/subjects/30.json"},{"id":21,"name":"Molecular Biology","url":"https://api.seqco.de/v1/subjects/21.json"}]}