Research progress on plant coumarin biosynthesis pathway and the genes encoding the key enzymes

doi:10.11686/cyxb2020485

Abstract

Abstract:

Coumarins， the important secondary metabolites of plants， derive from phenylpropanoids metabolism pathway， have a variety of biological activities and play an important role in plant growth and development and stress response. Here， the research progress of coumarin biosynthesis pathway and the genes encoding the key enzymes involved in coumarin biosynthesis were reviewed， and the phylogenetic evolution of the UDP-glucosyltransferase （UGT） gene family were analyzed. Moreover， the current research issues on coumarin biosynthesis were summarized and the future research directions were prospected in order to provide references for studying the coumarin biosynthesis and follow-up research.

Key words: coumarin, biosynthesis, genes encoding the key enzymes, UDP-glucosyltransferase, phylogenetic evolutionary

Zhen DUAN, Fan WU, Qi YAN, Ji-yu ZHANG. Research progress on plant coumarin biosynthesis pathway and the genes encoding the key enzymes[J]. Acta Prataculturae Sinica, 2022, 31(1): 217-228.

Figures/Tables 4

References 101

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名称 Name	主要功能和作用 Main functions	代表物种 Representative species	参考文献 Reference
苯丙氨酸解氨酶Phenylalanine ammonia-lyase，PAL	催化苯丙氨酸脱氨生成反式肉桂酸Catalyze phenylalanine into trans-cinnamic acid	白花前胡P. praeruptorum	［75］
肉桂酸2-羟化酶Cinnamic acid 2-hydroxylase，C2H	催化反式肉桂酸的邻羟基化Catalyze o-hydroxylation of trans-cinnamic acid	-	［64］
肉桂酸4-羟化酶Cinnamic acid 4-hydroxylase，C4H	催化肉桂酸C4羟基化形成对-羟基香豆酸Catalyze aromatic ring-4 hydroxylation of cinnamic acid into p-coumaric acid	紫花苜蓿Medicago sativa	［76］
4-香豆酸CoA连接酶4-coumarate CoA ligase，4CL	催化肉桂酸及其羟基或甲氧基衍生物生成相应的肉桂酸CoA酯Convert cinnamic acid and its hydroxy or methoxy derivates to corresponding cinnamate CoA thioesters	白花前胡P. praeruptorum	［77］
对香豆酰酯3’-羟化酶p-coumaroylshikimate/quinate 3-hydroxylase，C3’H	催化香豆酰奎尼酸和香豆酰莽草酸分别生成咖啡酰奎尼酸和咖啡酰莽草酸Catalyze p-coumaroyl shikimic acid and p-coumaroyl quinic acid to caffeoyl shikimic acid and caffeoyl quinic acid	芸香Ruta graveolens	［62，67］
香豆酸-3-羟基化酶4-coumarate-3-hydroxylase，C3H	催化对香豆酸的3位C的羟基化生成咖啡酸Hydroxylate p-coumaroyl ester derivatives at the ring-3 position， leading to caffeic acid	苎麻Boehmeria nivea	［78］
羟基肉桂酰基转移酶Hydroxycinnamoyl transferase，HCT	以对香豆酰辅酶A等多种酰基辅酶A作为酰基供体，催化莽草酸、奎尼酸等形成酰胺化合物Catalyze the synthesis of the shikimate and quinate esters of p-coumaric acid， using a variety of acyl coenzyme A， such as coumaryl coenzyme A as acyl donors	拟南芥A. thaliana	［79］
咖啡酸O-甲基转移酶Caffeic acid O-methyltransferase，COMT	催化咖啡酸生成阿魏酸Catalyze caffeic acid to ferulic acid	白花前胡P. praeruptorum	［80］
咖啡酰辅酶A O-甲基转移酶Caffeoyl CoA O-methyltransferase，CCoAOMT	催化咖啡酰CoA形成阿魏酰CoA Catalyze caffeoyl CoA to feruyl CoA	拟南芥A. thaliana	［68］
香豆酰CoA 2’-羟化酶p-coumaroyl CoA 2’-hydroxylase，C2’H	催化对香豆酰CoA发生邻羟基化形成2，4-二羟基香豆酰CoA Catalyze o-hydroxylation of coumaryl CoA to 2， 4-dihydroxy coumaryl CoA	芸香R. graveolens	［59-60］
阿魏酰-CoA 6’-羟化酶1 Feruloyl-CoA 6’-hydroxylase1，F6’H1	催化阿魏酰CoA芳香环脂肪侧链邻羟基化生成6-羟基阿魏酰CoA Catalyze hydroxylation of the fatty side chain of aromatic ring of feruyl-CoA to 6-hydroxylferuyl-CoA	拟南芥A. thaliana	［51，69］
香豆素合酶Coumarin synthase，COSY	催化顺-反异构化和内酯化 Catalyse trans-cis isomerization and lactonization	拟南芥A. thaliana	［61］
UDP-葡萄糖基转移酶UDP-glucosyltransferase，UGT	催化糖基化反应，将糖基从活化的供体分子转移到受体分子，形成相应的葡萄糖苷 Catalyzing the transfer of a glycosyl moiety from an activated donor to an acceptor molecule， forming corresponding glucoside	拟南芥A. thaliana	［81］
β-葡萄糖苷酶β-glucosidases，BGLU	催化碳水化合物部分和香豆素核心结构之间的β-葡萄糖苷键的水解，产生香豆素苷元形式 Catalyze the hydrolysis of the β-glucosidic bond between the carbohydrate portion and the coumarin core structure to produce the coumarin aglycone	玉米Z. mays	［66］
东莨菪内酯8-羟化酶Scopoletin 8-hydroxylase，S8H	催化东莨菪内酯的C8位羟基化转化为秦皮素 Catalyze hydroxylation of scopoletin at C8 position to fraxetin	拟南芥A. thaliana	［37，51，70］
O-甲基转移酶O-methyltransferase，OMT	催化七叶亭甲基化为东莨菪内酯Methylate esculetin generating scopoletin	钝鳞紫背藓Plagiochasma appendiculatum	［82］

名称 Name	主要功能和作用 Main functions	代表物种 Representative species	参考文献 Reference
苯丙氨酸解氨酶Phenylalanine ammonia-lyase，PAL	催化苯丙氨酸脱氨生成反式肉桂酸Catalyze phenylalanine into trans-cinnamic acid	白花前胡P. praeruptorum	［75］
肉桂酸2-羟化酶Cinnamic acid 2-hydroxylase，C2H	催化反式肉桂酸的邻羟基化Catalyze o-hydroxylation of trans-cinnamic acid	-	［64］
肉桂酸4-羟化酶Cinnamic acid 4-hydroxylase，C4H	催化肉桂酸C4羟基化形成对-羟基香豆酸Catalyze aromatic ring-4 hydroxylation of cinnamic acid into p-coumaric acid	紫花苜蓿Medicago sativa	［76］
4-香豆酸CoA连接酶4-coumarate CoA ligase，4CL	催化肉桂酸及其羟基或甲氧基衍生物生成相应的肉桂酸CoA酯Convert cinnamic acid and its hydroxy or methoxy derivates to corresponding cinnamate CoA thioesters	白花前胡P. praeruptorum	［77］
对香豆酰酯3’-羟化酶p-coumaroylshikimate/quinate 3-hydroxylase，C3’H	催化香豆酰奎尼酸和香豆酰莽草酸分别生成咖啡酰奎尼酸和咖啡酰莽草酸Catalyze p-coumaroyl shikimic acid and p-coumaroyl quinic acid to caffeoyl shikimic acid and caffeoyl quinic acid	芸香Ruta graveolens	［62，67］
香豆酸-3-羟基化酶4-coumarate-3-hydroxylase，C3H	催化对香豆酸的3位C的羟基化生成咖啡酸Hydroxylate p-coumaroyl ester derivatives at the ring-3 position， leading to caffeic acid	苎麻Boehmeria nivea	［78］
羟基肉桂酰基转移酶Hydroxycinnamoyl transferase，HCT	以对香豆酰辅酶A等多种酰基辅酶A作为酰基供体，催化莽草酸、奎尼酸等形成酰胺化合物Catalyze the synthesis of the shikimate and quinate esters of p-coumaric acid， using a variety of acyl coenzyme A， such as coumaryl coenzyme A as acyl donors	拟南芥A. thaliana	［79］
咖啡酸O-甲基转移酶Caffeic acid O-methyltransferase，COMT	催化咖啡酸生成阿魏酸Catalyze caffeic acid to ferulic acid	白花前胡P. praeruptorum	［80］
咖啡酰辅酶A O-甲基转移酶Caffeoyl CoA O-methyltransferase，CCoAOMT	催化咖啡酰CoA形成阿魏酰CoA Catalyze caffeoyl CoA to feruyl CoA	拟南芥A. thaliana	［68］
香豆酰CoA 2’-羟化酶p-coumaroyl CoA 2’-hydroxylase，C2’H	催化对香豆酰CoA发生邻羟基化形成2，4-二羟基香豆酰CoA Catalyze o-hydroxylation of coumaryl CoA to 2， 4-dihydroxy coumaryl CoA	芸香R. graveolens	［59-60］
阿魏酰-CoA 6’-羟化酶1 Feruloyl-CoA 6’-hydroxylase1，F6’H1	催化阿魏酰CoA芳香环脂肪侧链邻羟基化生成6-羟基阿魏酰CoA Catalyze hydroxylation of the fatty side chain of aromatic ring of feruyl-CoA to 6-hydroxylferuyl-CoA	拟南芥A. thaliana	［51，69］
香豆素合酶Coumarin synthase，COSY	催化顺-反异构化和内酯化 Catalyse trans-cis isomerization and lactonization	拟南芥A. thaliana	［61］
UDP-葡萄糖基转移酶UDP-glucosyltransferase，UGT	催化糖基化反应，将糖基从活化的供体分子转移到受体分子，形成相应的葡萄糖苷 Catalyzing the transfer of a glycosyl moiety from an activated donor to an acceptor molecule， forming corresponding glucoside	拟南芥A. thaliana	［81］
β-葡萄糖苷酶β-glucosidases，BGLU	催化碳水化合物部分和香豆素核心结构之间的β-葡萄糖苷键的水解，产生香豆素苷元形式 Catalyze the hydrolysis of the β-glucosidic bond between the carbohydrate portion and the coumarin core structure to produce the coumarin aglycone	玉米Z. mays	［66］
东莨菪内酯8-羟化酶Scopoletin 8-hydroxylase，S8H	催化东莨菪内酯的C8位羟基化转化为秦皮素 Catalyze hydroxylation of scopoletin at C8 position to fraxetin	拟南芥A. thaliana	［37，51，70］
O-甲基转移酶O-methyltransferase，OMT	催化七叶亭甲基化为东莨菪内酯Methylate esculetin generating scopoletin	钝鳞紫背藓Plagiochasma appendiculatum	［82］

基因 Gene	物种Species
基因 Gene	拟南芥^［91］ A. thaliana	水稻^［92］ O. sativa	蒺藜苜蓿^［93］ M. truncatula
PAL	4	9	4
C3H	8	15	2
C4H	1	4	1
4CL	11	10	13
CCoAOMT	7	6	3
COMT	10	3	16
HCT	5	2	11
2OGD	17	15	19
BGLU	48	40	45
UGT	121	178	243

基因 Gene	物种Species
基因 Gene	拟南芥^［91］ A. thaliana	水稻^［92］ O. sativa	蒺藜苜蓿^［93］ M. truncatula
PAL	4	9	4
C3H	8	15	2
C4H	1	4	1
4CL	11	10	13
CCoAOMT	7	6	3
COMT	10	3	16
HCT	5	2	11
2OGD	17	15	19
BGLU	48	40	45
UGT	121	178	243

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[2]	WU Cai-xia,LIU Su-jiao,ZHAO Guo-qi. Isolation and identification of the potential allelochemicals in the aqueous extract of yellow sweet clover (Melilotus officinalis) [J]. Acta Prataculturae Sinica, 2014, 23(5): 184-192.