Cobalamin production by Lactobacillus coryniformis: biochemical identification of the synthetized corrinoid and genomic analysis of the biosynthetic cluster.
Cobalamin production by Lactobacillus coryniformis: biochemical identification of the synthetized corrinoid and genomic analysis of the biosynthetic cluster.
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DOI：
10.1186/s12866-016-0854-9
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发表时间：
2016-10-13
期刊：
影响因子：
4.2
通讯作者：
Taranto MP
中科院分区：
文献类型：
--
作者：
Torres AC;Vannini V;Bonacina J;Font G;Saavedra L;Taranto MP
尽管大多数维生素存在于各种食物中，但营养不良、饮食不平衡或食物摄入不足仍然是一些国家人类维生素缺乏症的原因。维生素B12（钴胺素）是一种复杂的化合物，仅由细菌和古细菌天然产生。据报道，属于乳酸菌群的某些菌株能够合成水溶性维生素，如B群中所包括的那些，如维生素B12。在这种情况下，本文的目标是评估和表征的生产维生素B12在棒状乳杆菌CRL 1001，从青贮饲料中分离的异型发酵菌株。L.从青贮饲料中分离的coryniformis CRL 1001能够在基本培养基中校正沙门氏菌鼠伤寒血清型AR 2680对辅酶B12的需求。本文报道了从CRL 1001细胞提取物中分离得到的类咕啉样分子的化学特性。该菌株产生的类可啉化合物中大部分以腺嘌呤样Coα-配体取代5，6-二甲基苯并咪唑。基因组研究揭示了辅酶B12厌氧生物合成途径的完整机制的存在。检测到的基因编码用于咕啉环生物合成和用于在染色体的一个连续延伸中结合上（β）和下（α）配体的所有蛋白质。本文的结果首次表明L.棒形亚种Coryniformis CRL 1001能产生含有腺嘌呤的伪钴胺素，而Coα-配体中含有5，6-二甲基苯并咪唑。基因组分析允许鉴定和表征由CRL 1001菌株产生的类咕啉的完整从头生物合成途径。
Despite the fact that most vitamins are present in a variety of foods, malnutrition, unbalanced diets or insufficient intake of foods are still the cause of vitamin deficiencies in humans in some countries. Vitamin B12 (Cobalamin) is a complex compound that is only naturally produced by bacteria and archea. It has been reported that certain strains belonging to lactic acid bacteria group are capable of synthesized water-soluble vitamins such as those included in the B-group, as vitamin B12. In this context, the goal of the present paper was to evaluate and characterize the production of vitamin B12 in Lactobacillus coryniformis CRL 1001, a heterofermentative strain isolated from silage. Cell extract of L. coryniformis CRL 1001, isolated from silage, is able to correct the coenzyme B12 requirement of Salmonella enterica serovar Typhimurium AR 2680 in minimal medium. The chemical characterization of the corrinoid-like molecule isolated from CRL 1001 cell extract using HPLC and mass spectrometry is reported. The majority of the corrinoid produced by this strain has adenine like Coα-ligand instead 5,6-dimethylbenzimidazole. Genomic studies revealed the presence of the complete machinery of the anaerobic biosynthesis pathway of coenzyme B12. The detected genes encode all proteins for the corrin ring biosynthesis and for the binding of upper (β) and lower (α) ligands in one continuous stretch of the chromosome. The results here described show for the first time that L. coryniformis subsp. coryniformis CRL 1001 is able to produce pseudocobalamin containing adenine instead of 5,6-dimethlbenzimidazole in the Coα-ligand. Genomic analysis allowed the identification and characterization of the complete de novo biosynthetic pathway of the corrinoid produced by the CRL 1001 strain.