An unexplored pathway for degradation of cholate requires a 7α-hydroxysteroid dehydratase and contributes to a broad metabolic repertoire for the utilization of bile salts in Novosphingobium sp. strain Chol11.
An unexplored pathway for degradation of cholate requires a 7α-hydroxysteroid dehydratase and contributes to a broad metabolic repertoire for the utilization of bile salts in Novosphingobium sp. strain Chol11.
复制标题
胆酸盐降解的未经探索的途径需要 7α-羟基类固醇脱水酶，并有助于在新鞘氨醇 sp 菌株 Chol11 中利用胆汁盐的广泛代谢库
DOI：
10.1111/1462-2920.13534
复制
发表时间：
--
影响因子：
5.1
通讯作者：
Philipp
中科院分区：
文献类型：
--
作者：
Yücel;Jagmann;Patschkowski;Philipp
胆汁盐（如胆酸盐）是具有表面活性的类固醇化合物，在脊椎动物中具有消化和信号传导功能。在排泄到土壤和水中后，胆汁盐是环境细菌的富含电子和碳的生长基质。胆盐的降解通过类固醇骨架的3-酮-Δ 1，4-二烯结构的中间体进行，如假单胞菌属所示。最近，我们分离出通过具有类固醇骨架的3-酮-7-脱氧-Δ 4，6-结构的中间体降解胆酸盐的细菌，这表明存在胆酸盐降解的第二途径。利用Novosphingobiumsp.菌株Chol 11。鉴定了由hsh 2编码的7α-羟基类固醇脱氢酶，其是形成3-酮-7-脱氧-Δ 4，6-代谢物所必需的。Ahsh 2缺失突变体仍能与胆酸盐一起生长，但表现出受损的生长。该突变体的胆酸盐降解通过3-酮-Δ 1，4-二烯代谢物进行。Hsh 2在胆盐降解假单胞菌中的异质性表达。菌株Chol 1导致形成具有3-酮基-7-脱氧-Δ 4，6-二烯结构的死端类固醇。Hsh 2是第一个在以胆盐为生长底物的细菌代谢途径中具有重要功能的类固醇脱氢酶。该途径有助于新鞘氨醇菌菌株Chol 11的广泛代谢谱，这可能有利于与其他胆盐降解细菌竞争。
Bile salts such as cholate are surface‐active steroid compounds with functions for digestion and signaling in vertebrates. Upon excretion into soil and water bile salts are an electron‐ and carbon‐rich growth substrate for environmental bacteria. Degradation of bile salts proceeds via intermediates with a 3‐keto‐Δ1,4‐diene structure of the steroid skeleton as shown for e.g.Pseudomonasspp. Recently, we isolated bacteria degrading cholate via intermediates with a 3‐keto‐7‐deoxy‐Δ4,6‐structure of the steroid skeleton suggesting the existence of a second pathway for cholate degradation. This potential new pathway was investigated withNovosphingobiumsp. strain Chol11. A 7α‐hydroxysteroid dehydratase encoded byhsh2was identified, which was required for the formation of 3‐keto‐7‐deoxy‐Δ4,6‐metabolites. Ahsh2deletion mutant could still grow with cholate but showed impaired growth. Cholate degradation of this mutant proceeded via 3‐keto‐Δ1,4‐diene metabolites. Heterologous expression of Hsh2 in the bile salt‐degradingPseudomonassp. strain Chol1 led to the formation of a dead‐end steroid with a 3‐keto‐7‐deoxy‐Δ4,6‐diene structure. Hsh2 is the first steroid dehydratase with an important function in a metabolic pathway of bacteria that use bile salts as growth substrates. This pathway contributes to a broad metabolic repertoire ofNovosphingobiumstrain Chol11 that may be advantageous in competition with other bile salt‐degrading bacteria.
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胆汁盐作为生物表面活性剂
DOI：
--
发表时间：
1987
期刊：
影响因子：
--
作者：
A. Hofmann;K. J. Mysels
通讯作者：
K. J. Mysels
影响因子：
5.1
作者：
Holert, Johannes;Yuecel, Onur;Philipp, Bodo
通讯作者：
Philipp, Bodo
影响因子：
2.7
作者：
E. Mukherjee;Sukdeb Banerjee;S. Mahato
通讯作者：
S. Mahato
影响因子：
5.1
作者：
Jagmann, Nina;Brachvogel, Hans-Philipp;Philipp, Bodo
通讯作者：
Philipp, Bodo
影响因子：
3.2
作者：
Holert, Johannes;Kulic, Zarko;Philipp, Bodo
通讯作者：
Philipp, Bodo