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Information on EC 2.5.1.45 - homospermidine synthase (spermidine-specific)
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2.5.1.45 homospermidine synthase (spermidine-specific)IUBMB Comments
A eukaryotic enzyme found in plants. The reaction occurs in three steps, with some of the intermediates presumably remaining enzyme-bound: (a) NAD+-dependent dehydrogenation of spermidine to 4-iminobutan-1-amine, (b) attack by water forming 4-aminobutanal (and releasing propane-1,3-diamine), and (c) condensation of 4-aminobutanal with purescine, which forms homospermidine and restores NAD+. This enzyme is more specific than EC 2.5.1.44, homospermidine synthase, which is found in bacteria, as it cannot use putrescine as donor of the 4-aminobutyl group. Forms part of the biosynthetic pathway of the poisonous pyrrolizidine alkaloids of the ragworts (Senecio).
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The expected taxonomic range for this enzyme is: Bacteria, Eukaryota, Archaea
Synonyms
homospermidine synthase, HSS, HSS1, synthase, homospermidine, synthase, homospermidine (Senecio vernalis root gene HSS1), 
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
homospermidine synthase
HSS
synthase, homospermidine
-
-
-
-
synthase, homospermidine (Senecio vernalis root gene HSS1)
-
-
-
-
HSS
-
-
-
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
spermidine + putrescine = sym-homospermidine + propane-1,3-diamine
the reaction of this enzyme occurs in three steps: i. NAD-dependent dehydrogenation of spermidine, ii. transfer of the 4-aminobutylidene group from dehydrospermidine to putrescine, iii. reduction of the imine intermediate to form homospermidine. Hence the overall reaction is transfer of a 4-aminobutyl group. This enzyme is more specific than EC 2.5.1.44, homospermidine synthase, which is found in bacteria, as it cannot use putrescine as donor of the 4-aminobutyl group. Forms part of the biosynthetic pathway of the poisonous pyrrolizidine alkaloids of the ragworts, Senecio
-
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
aminobutyl group transfer
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
-
-
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SYSTEMATIC NAME
IUBMB Comments
spermidine:putrescine 4-aminobutyltransferase (propane-1,3-diamine-forming)
A eukaryotic enzyme found in plants. The reaction occurs in three steps, with some of the intermediates presumably remaining enzyme-bound: (a) NAD+-dependent dehydrogenation of spermidine to 4-iminobutan-1-amine, (b) attack by water forming 4-aminobutanal (and releasing propane-1,3-diamine), and (c) condensation of 4-aminobutanal with purescine, which forms homospermidine and restores NAD+. This enzyme is more specific than EC 2.5.1.44, homospermidine synthase, which is found in bacteria, as it cannot use putrescine as donor of the 4-aminobutyl group. Forms part of the biosynthetic pathway of the poisonous pyrrolizidine alkaloids of the ragworts (Senecio).
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CAS REGISTRY NUMBER
COMMENTARY
259168-77-9
-
76106-84-8
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
Eupatorium pauciflorum
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
-
-
-
?
putrescine + spermidine
N-(4-aminobutyl)butane-1,4-diamine + propane-1,3-diamine
the plant homospermidine synthase is essentially dependent on spermidine as aminobutyl donor and is unable to synthesize homospermidine from two molecules of putrescine
-
?
putrescine + spermidine
sym-homospermidine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
sym-homospermidine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
Eupatorium pauciflorum
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
the plant homospermidine synthase is essentially dependent on spermidine as aminobutyl donor and is unable to synthesize homospermidine from two molecules of putrescine
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
first specific enzyme in the biosynthesis of the necine base moiety of pyrrolizidine alkaloids
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
first specific enzyme in the biosynthesis of the necine base moiety of pyrrolizidine alkaloids
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
putrescine + spermidine
sym-homospermidine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermidine
sym-homospermidine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
Eupatorium pauciflorum
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
-
-
-
-
?
putrescine + spermine
sym-homospermine + propane-1,3-diamine
the plant homospermidine synthase is essentially dependent on spermidine as aminobutyl donor and is unable to synthesize homospermidine from two molecules of putrescine
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
first specific enzyme in the biosynthesis of the necine base moiety of pyrrolizidine alkaloids
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
first specific enzyme in the biosynthesis of the necine base moiety of pyrrolizidine alkaloids
-
-
?
spermidine + putrescine
sym-homospermidine + propane-1,3-diamine
-
-
-
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
NAD+
-
the NADH formed in the first part of the reaction, i.e. oxidative deamination of putrescine, is cosubstrate of the second part of the reaction, i.e. hydrogenation of an intermolecular Schiff's base between the semialdehyde in the reaction and the second putrescine unit
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.003
NAD+
-
NAD+ functions as an enzyme-bound redoxsystem that is reduced in the first and reoxidized in the second part of the overall reaction. It functions as a coenzyme and not a cosubstrate
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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Ki VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.047
0.062
-
purified recombinant enzyme, pH and temperature not specified in the publication
0.136
-
purified recombinant enzyme, pH and temperature not specified in the publication
0.138
0.047
-
purified recombinant enzyme, pH and temperature not specified in the publication
0.138
-
purified recombinant enzyme, pH and temperature not specified in the publication
0.138
-
purified recombinant enzyme, pH and temperature not specified in the publication
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
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SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
SOURCE
-
young flower buds, but not mature flowers, express homospermidine synthase and are able to catalyze pyrrolizidine alkaloid biosynthesis
brenda
additional information
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
-
HSS is expressed exclusively in nonspecialized cells of the lower epidermis of young leaves and shoots
brenda
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
-
HSS expression in leaves directly underneath developing inflorescences
brenda
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
plants activate a second site of HSS expression when inflorescences start to develop. HSS is localized in the bundle sheath cells of young leaves, which express the whole pyrrolizidine alkaloids biosynthetic route
brenda
from lower epidermis of leaf and stem, no activity in upper epidermis cells
brenda
from lower epidermis of leaf and stem, no activity in upper epidermis cells
brenda
from lower epidermis of leaf and stem, no activity in upper epidermis cells
brenda
-
in young roots, HSS is detected only in cells of the endodermis, but in a later developmental stage, additionally in the pericycle
brenda
-
gene expression is restricted to young root. Expressed uniformly in all cells of the root cortex parenchyma, but not within the endodermis and exodermis
brenda
-
gene expression is restricted to young root. Expressed uniformly in all cells of the root cortex parenchyma, but not within the endodermis and exodermis
brenda
-
expressed in the tips of aerial roots exclusively in mitotically active cells. Raphide crystal idioblasts present within the root apical meristem do not show expression
brenda
-
in the roots of Eupatorium cannabinum, all cells of the cortex parenchyma are found to express HSS, but not the cells of the endodermis
brenda
-
HSS is expressed exclusively in nonspecialized cells of the lower epidermis of young leaves and shoots
brenda
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
the enzyme is expressed only in the cells of the lower leaf epidermis and the epidermis of the stem
brenda
additional information
-
the tissue-specific expression of HSS in this boraginaceous species is unique with respect to plant organ, tissue, and cell type, expression patterns, immunohistochemic analysis and semiquantitative RT-PCR, overview
brenda
additional information
-
tissue-specific expression of enzyme HSS
brenda
additional information
-
the tissue-specific expression of HSS in this boraginaceous species is unique with respect to plant organ, tissue, and cell type, expression patterns, immunohistochemic analysis and semiquantitative RT-PCR, overview
brenda
additional information
-
not expressed in the aerial parts of the plant like buds, flower heads, leaves, or stems
brenda
additional information
-
the tissue-specific expression of HSS in this boraginaceous species is unique with respect to plant organ, tissue, and cell type, expression patterns, immunohistochemic analysis and semiquantitative RT-PCR, overview
brenda
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LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
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GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
evolution
malfunction
-
transgenic tobacco plants are generated expressing Senecio vernalis homospermidine synthase. Analyses of the polyamine content reveals that, in the transgenic plants, about 80% of spermidine is replaced by homospermidine without any conspicuous modifications of the phenotype. Tracer-feeding experiments and gas chromatographic analyses suggest that these high levels of homospermidine are not sufficient to explain the formation of alkaloid precursors
metabolism
physiological function
additional information
evolution
-
the gene encoding enzyme HSS origins from a single duplication event of a single-copy gene encoding deoxyhypusine synthase, DHS, EC 2.5.1.46. This duplication event was followed by several losses of a functional gene copy attributable to gene loss or pseudogenization. Statistical analyses of sequence data suggest that, in those lineages in which the gene copy was successfully recruited as HSS, the gene duplication event was followed by phases of various selection pressures, including purifying selection, relaxed functional constraints, and possibly positive Darwinian selection
evolution
-
the gene encoding enzyme HSS origins from a single duplication event of a single-copy gene encoding deoxyhypusine synthase, DHS, EC 2.5.1.46. This duplication event was followed by several losses of a functional gene copy attributable to gene loss or pseudogenization. Statistical analyses of sequence data suggest that, in those lineages in which the gene copy was successfully recruited as HSS, the gene duplication event was followed by phases of various selection pressures, including purifying selection, relaxed functional constraints, and possibly positive Darwinian selection
evolution
-
the gene encoding enzyme HSS origins from a single duplication event of a single-copy gene encoding deoxyhypusine synthase, DHS, EC 2.5.1.46. This duplication event was followed by several losses of a functional gene copy attributable to gene loss or pseudogenization. Statistical analyses of sequence data suggest that, in those lineages in which the gene copy was successfully recruited as HSS, the gene duplication event was followed by phases of various selection pressures, including purifying selection, relaxed functional constraints, and possibly positive Darwinian selection
evolution
-
the gene encoding enzyme HSS origins from a single duplication event of a single-copy gene encoding deoxyhypusine synthase, DHS, EC 2.5.1.46. This duplication event was followed by several losses of a functional gene copy attributable to gene loss or pseudogenization. Statistical analyses of sequence data suggest that, in those lineages in which the gene copy was successfully recruited as HSS, the gene duplication event was followed by phases of various selection pressures, including purifying selection, relaxed functional constraints, and possibly positive Darwinian selection
evolution
-
the gene encoding enzyme HSS origins from a single duplication event of a single-copy gene encoding deoxyhypusine synthase, DHS, EC 2.5.1.46. This duplication event was followed by several losses of a functional gene copy attributable to gene loss or pseudogenization. Statistical analyses of sequence data suggest that, in those lineages in which the gene copy was successfully recruited as HSS, the gene duplication event was followed by phases of various selection pressures, including purifying selection, relaxed functional constraints, and possibly positive Darwinian selection
metabolism
-
homospermidine synthase is the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis
metabolism
-
homospermidine synthase is the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis
metabolism
-
homospermidine synthase is the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis
metabolism
-
homospermidine synthase is the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis
metabolism
-
homospermidine synthase is the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis
metabolism
polymanines in Crotalaria are detectable only when the plants form nodules after infection with their rhizobial partner. But polyamines are synthesized by the plant not by the mcirosymbiont
metabolism
the enzyme is first specific enzyme in the biosynthesis of pyrrolizidine alkaloids
metabolism
the enzyme is first specific enzyme in the biosynthesis of pyrrolizidine alkaloids
metabolism
the enzyme is first specific enzyme in the biosynthesis of pyrrolizidine alkaloids, it is involved in the biosynthetic pathway of the lycopsamine-type polyamine indicine N-oxide
physiological function
RNAi knockdown of HSS in hairy roots by 60-80% results in a reduction of homospermidine by about 86% and of the major pyrrolizidine alkaloid components 7-acetylintermedine N-oxide and 3-acetylmyoscorpine N-oxide by approximately 60%
physiological function
the gene encoding isoform HSS1 is absent in some perennial ryegrass plants, and absence of the HSS1 gene is associated with lower levels of thesinine-rhamnoside pyrrolizidine alkaloids
additional information
exogenously applied nitrate has no impact on polyamine biosynthesis, and enzyme activity, but nodulation is inhibited at higher levels of nitrate by autoregulation
additional information
-
the Convulvulaceae species Ipomoea alba contains ipanguline-type polyamines. Detection of sites that are involved in optimizing HSS functionality
additional information
-
the Convulvulaceae species Ipomoea hederifolia contains ipanguline-type polyamines. Detection of sites that are involved in optimizing HSS functionality
additional information
-
the Convulvulaceae species Ipomoea meyeri contains ipanguline- and triangularine-type polyamines. Detection of sites that are involved in optimizing HSS functionality
additional information
-
the Convulvulaceae species Ipomoea neei contains ipanguline-type polyamines. Detection of sites that are involved in optimizing HSS functionality
additional information
-
the Convulvulaceae species Merremia quinquefolia contains ipanguline- and triangularine-type polyamines. Detection of sites that are involved in optimizing HSS functionality
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UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). HSS1_SENVE
370
0
40726
Swiss-Prot
other Location (Reliability: 2)
HSS1_SENVU
370
0
40740
Swiss-Prot
other Location (Reliability: 2)
HSS2_SENVE
370
0
40733
Swiss-Prot
other Location (Reliability: 2)
I3Z8K6_BELBD
Belliella baltica (strain DSM 15883 / CIP 108006 / LMG 21964 / BA134)
323
0
36304
TrEMBL
-
A0A0B6WU12_9BACT
325
0
36760
TrEMBL
-
R4ZGM5_9ASTE
376
0
41591
TrEMBL
other Location (Reliability: 2)
Q5ZN66_CYNOF
369
0
40691
TrEMBL
other Location (Reliability: 3)
Q5ZN58_9ASPA
371
0
40378
TrEMBL
other Location (Reliability: 3)
A0A0E4G3W1_9FABA
370
0
40998
TrEMBL
other Location (Reliability: 2)
Q1IQA7_KORVE
Koribacter versatilis (strain Ellin345)
357
0
39614
TrEMBL
-
A0A062V9Q5_9EURY
376
0
40931
TrEMBL
-
A0A6N4SSA4_CYTH3
Cytophaga hutchinsonii (strain ATCC 33406 / DSM 1761 / CIP 103989 / NBRC 15051 / NCIMB 9469 / D465)
324
0
37012
TrEMBL
-
R4ZGM0_IPOAL
356
0
39266
TrEMBL
other Location (Reliability: 3)
B9SW18_RICCO
366
0
40496
TrEMBL
other Location (Reliability: 2)
Q5ZN59_PETHB
369
0
40657
TrEMBL
other Location (Reliability: 3)
A0A6N3IX89_DISTU
284
0
31662
TrEMBL
other Location (Reliability: 2)
A0A075MV88_9ARCH
373
0
41109
TrEMBL
-
Q5ZN64_EUPCN
375
0
41647
TrEMBL
other Location (Reliability: 4)
R4ZGP1_9ASTE
373
0
41286
TrEMBL
other Location (Reliability: 2)
A0A2U3JXB9_9BACT
386
0
42515
TrEMBL
-
A0A6N3IVX8_9ASTE
355
0
39171
TrEMBL
other Location (Reliability: 3)
I3YTK6_AEQSU
Aequorivita sublithincola (strain DSM 14238 / LMG 21431 / ACAM 643 / 9-3)
325
0
36821
TrEMBL
-
R4ZGM6_9ASTE
376
0
41562
TrEMBL
other Location (Reliability: 2)
C4PLB2_PHAAB
371
0
40195
TrEMBL
other Location (Reliability: 3)
G8THF5_NIAKG
Niastella koreensis (strain DSM 17620 / KACC 11465 / NBRC 106392 / GR20-10)
324
0
36706
TrEMBL
-
A0A6M4MJ07_9ASTE
376
0
41607
TrEMBL
other Location (Reliability: 2)
Q5ZN55_SYMOF
375
0
41270
TrEMBL
Chloroplast (Reliability: 5)
Q5ZN63_9ASTE
364
0
40081
TrEMBL
other Location (Reliability: 1)
Q5ZN56_JACVU
372
0
40941
TrEMBL
other Location (Reliability: 2)
F0SR06_RUBBR
Rubinisphaera brasiliensis (strain ATCC 49424 / DSM 5305 / JCM 21570 / IAM 15109 / NBRC 103401 / IFAM 1448)
324
0
36510
TrEMBL
-
R4ZGQ1_9ASTE
376
0
41546
TrEMBL
other Location (Reliability: 2)
E6XE54_CELAD
Cellulophaga algicola (strain DSM 14237 / IC166 / ACAM 630)
325
0
36806
TrEMBL
-
A0A8B0MCC9_SYMOF
375
0
41212
TrEMBL
Chloroplast (Reliability: 5)
R4ZGM3_9ASTE
376
0
41460
TrEMBL
other Location (Reliability: 2)
Q5ZN57_SENVE
370
0
40733
TrEMBL
other Location (Reliability: 2)
A0A6M4MIS3_9ASTE
178
0
19160
TrEMBL
other Location (Reliability: 4)
A0A6M4MKB5_9ASTE
359
0
39742
TrEMBL
other Location (Reliability: 2)
A0A6M4MJB9_9ASTE
377
0
41867
TrEMBL
other Location (Reliability: 2)
H2BRV4_GILLR
Gillisia limnaea (strain DSM 15749 / LMG 21470 / R-8282)
323
0
36512
TrEMBL
-
E4TKH9_MARTH
Marivirga tractuosa (strain ATCC 23168 / DSM 4126 / NBRC 15989 / NCIMB 1408 / VKM B-1430 / H-43)
321
0
36364
TrEMBL
-
R4ZGP2_IPOAL
376
0
41528
TrEMBL
other Location (Reliability: 2)
F0S657_PSESL
Pseudopedobacter saltans (strain ATCC 51119 / DSM 12145 / JCM 21818 / CCUG 39354 / LMG 10337 / NBRC 100064 / NCIMB 13643)
326
0
36938
TrEMBL
-
A0A6N3IVQ9_9ASTE
368
0
40814
TrEMBL
other Location (Reliability: 2)
R4ZGN8_9ASTE
376
0
41466
TrEMBL
other Location (Reliability: 2)
Q2IE58_ANADE
Anaeromyxobacter dehalogenans (strain 2CP-C)
340
0
37772
TrEMBL
-
I4A244_ORNRL
Ornithobacterium rhinotracheale (strain ATCC 51463 / DSM 15997 / CCUG 23171 / CIP 104009 / LMG 9086)
321
0
36482
TrEMBL
-
A0A084G3F3_PSEDA
549
0
60814
TrEMBL
other Location (Reliability: 2)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
41500
41600
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
tetramer
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
I277D
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine and slightly reduced deoxyhypusine synthase activity compared to the wild-type
I277D/N281D
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine and reduced deoxyhypusine synthase activity compared to the wild-type
N266H
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine and reduced deoxyhypusine synthase activity compared to the wild-type
N266H/I277D
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine, but unaltered deoxyhypusine synthase activity compared to the wild-type
N266H/I277D/N281D
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine and reduced deoxyhypusine synthase activity compared to the wild-type
N266H/N281D
-
site-directed mutagenesis, the mutant shows increased HSS activity with putrescine and reduced deoxyhypusine synthase activity compared to the wild-type
N281D
-
site-directed mutagenesis, the mutant shows slightly reduced HSS activity with putrescine and reduced deoxyhypusine synthase activity compared to the wild-type
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GENERAL STABILITY
ORGANISM
UNIPROT
LITERATURE
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
4°C, crude extract, 0.5-1 mM spermidine, 0.5-1 mM NAD+, 1 week, 30% loss of activity
-
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
recombinant tagged enzyme from Escherichia coli by affinity chromatography
recombinant tagged enzyme from Escherichia coli by affinity chromatography
-
recombinant tagged enzyme from Escherichia coli by affinity chromatography
-
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expressed in Escherichia coli
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
gene HSS, semiquantitative RT-PCR expression analysis in tissues
gene hss1, DNA and amino acid sequence determination and analysis, cloning from cDNA library of lower leaf epidermis cells from leaves and stems, quantitative real-time PCR expression analysis in epidermis cells
gene hss1, DNA and amino acid sequence determination and analysis, sequence comparissons, quantitative real-time PCR enzyme expression analysis
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
-
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
-
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
-
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
-
gene hss, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic analysis, recombinant expression of tagged enzyme in Escherichia coli
-
gene hss1, DNA and amino acid sequence determination and analysis, cloning from cDNA library of lower leaf epidermis cells from leaves and stems, quantitative real-time PCR expression analysis in epidermis cells
gene hss1, DNA and amino acid sequence determination and analysis, cloning from cDNA library of lower leaf epidermis cells from leaves and stems, quantitative real-time PCR expression analysis in epidermis cells
gene hss1, DNA and amino acid sequence determination and analysis, cloning from cDNA library of lower leaf epidermis cells from leaves and stems, quantitative real-time PCR expression analysis in epidermis cells
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EXPRESSION
ORGANISM
UNIPROT
LITERATURE
exogenously applied nitrate has no impact on polyamine biosynthesis, and enzyme expression
no effect on enzyme expression by methyl jasmonate
polymanines in Crotalaria are detectable only when the plants form nodules after infection with their rhizobial partner, nodulation is induced by infection with a Bradyrhizobium strain and triggers the polyamine biosynthesis, leading to induction of the enzyme HSS in nodules
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Bttcher, F.; Ober, D.; Hartmann, T.
Biosynthesis of pyrrolizidine alkaloids: putrescine and spermidine are essential substrates of enzymatic homospermidine formation
Can. J. Chem.
72
80-85
1994
Eupatorium cannabinum
-
brenda
Ober, D.; Hartmann, T.
Homospermidine synthase, the first pathway-specific enzyme of pyrrolizidine alkaloid biosynthesis, evolved form deoxyhypusine synthase
Proc. Natl. Acad. Sci. USA
96
14777-14782
1999
Senecio vernalis (Q9SC13)
brenda
Ober, D.; Harms, R.; Witte, L.; Hartmann, T.
Molecular evolution by change of function. Alkaloid-specific homospermidine synthase retains all properties of deoxyhypusine synthase except binding the eIF5A precursor protein
J. Biol. Chem.
278
12805-12812
2003
Senecio vernalis
brenda
Moll, S.; Anke, S.; Kahmann, U.; Hnsch, R.; Hartmann, T.; Ober, D.
Cell-specific expression of homospermidine synthase, the entry enzyme of the pyrrolizidine alkaloid pathway in Senecio vernalis, in comparison with its ancestor, deoxyhypusine synthase
Plant Physiol.
130
47-57
2002
Senecio vernalis
brenda
Ober, D.; Harms, R.; Hartmann, T.
Cloning and expression of homospermidine synthase from Senecio vulgaris: a revision
Phytochemistry
55
305-309
2000
Senecio vulgaris (Q9M4B0)
brenda
Bttcher, F.; Adolph, R.D.; Hartmann, T.
Homospermidine synthase, the first pathway-specific enzyme in pyrrolizidine alkaloid biosynthesis
Phytochemistry
32
679-689
1993
Eupatorium cannabinum, Eupatorium pauciflorum, Jacobaea vulgaris
-
brenda
Graser, G.; Hartmann, T.
Biosynthetic incorporation of the aminobutyl group of spermidine into pyrrolizidine alkaloids
Phytochemistry
45
1591-1595
1997
Senecio vulgaris
-
brenda
Graser, G.; Witte, L.; Robins, D.J.; Hartmann, T.
Incorporation of chirally deuterated putrescines into pyrrolizidine alkaloids: a reinvestigation
Phytochemistry
47
1017-1024
1998
Senecio vulgaris
-
brenda
Nurhayati, N.; Ober, D.
Recruitment of alkaloid-specific homospermidine synthase (HSS) from ubiquitous deoxyhypusine synthase: Does Crotalaria possess a functional HSS that still has DHS activity?
Phytochemistry
66
1346-1357
2005
Crotalaria juncea, Phalaenopsis hybrid cultivar (Q5ZN58)
brenda
Anke, S.; Niemuller, D.; Moll, S.; Hansch, R.; Ober, D.
Polyphyletic origin of pyrrolizidine alkaloids within the Asteraceae. Evidence from differential tissue expression of homospermidine synthase
Plant Physiol.
136
4037-4047
2004
Eupatorium cannabinum, Jacobaea vulgaris
brenda
Froelich, C.; Ober, D.; Hartmann, T.
Tissue distribution, core biosynthesis and diversification of pyrrolizidine alkaloids of the lycopsamine type in three Boraginaceae species
Phytochemistry
68
1026-1037
2007
Heliotropium indicum
brenda
Anke, S.; Gonde, D.; Kaltenegger, E.; Haensch, R.; Theuring, C.; Ober, D.
Pyrrolizidine alkaloid biosynthesis in phalaenopsis orchids: developmental expression of alkaloid-specific homospermidine synthase in root tips and young flower buds
Plant Physiol.
148
751-760
2008
Phalaenopsis sp.
brenda
Ober, D.; Kaltenegger, E.
Pyrrolizidine alkaloid biosynthesis, evolution of a pathway in plant secondary metabolism
Phytochemistry
70
1687-1695
2009
Senecio vernalis, Phalaenopsis sp.
brenda
Nurhayati, N.; Gonde, D.; Ober, D.
Evolution of pyrrolizidine alkaloids in Phalaenopsis orchids and other monocotyledons: identification of deoxyhypusine synthase, homospermidine synthase and related pseudogenes
Phytochemistry
70
508-516
2009
Phalaenopsis sp.
brenda
Abdelhady, M.; Beuerle, T.; Ober, D.
Homospermidine in transgenic tobacco results in considerably reduced spermidine levels but is not converted to pyrrolizidine alkaloid precursors
Plant Mol. Biol.
71
145-155
2009
Senecio vernalis
brenda
Niemueller, D.; Reimann, A.; Ober, D.
Distinct cell-specific expression of homospermidine synthase involved in pyrrolizidine alkaloid biosynthesis in three species of the boraginales
Plant Physiol.
159
920-929
2012
Heliotropium indicum, Symphytum officinale, Cynoglossum officinale
brenda
Sievert, C.; Beuerle, T.; Hollmann, J.; Ober, D.
Single cell subtractive transcriptomics for identification of cell-specifically expressed candidate genes of pyrrolizidine alkaloid biosynthesis
Phytochemistry
117
17-24
2015
Symphytum officinale (Q5ZN55), Heliotropium indicum (Q5ZN63), Cynoglossum officinale (Q5ZN66)
brenda
Kaltenegger, E.; Eich, E.; Ober, D.
Evolution of homospermidine synthase in the convolvulaceae: a story of gene duplication, gene loss, and periods of various selection pressures
Plant Cell
25
1213-1227
2013
Ipomoea neei, Ipomoea hederifolia, Ipomoea alba, Ipomoea meyeri, Distimake quinquefolius
brenda
Irmer, S.; Podzun, N.; Langel, D.; Heidemann, F.; Kaltenegger, E.; Schemmerling, B.; Geilfus, C.M.; Zoerb, C.; Ober, D.
New aspect of plant-rhizobia interaction: alkaloid biosynthesis in Crotalaria depends on nodulation
Proc. Natl. Acad. Sci. USA
112
4164-4169
2015
Crotalaria spectabilis (A0A0E4G3W1)
brenda
Gill, G.P.; Bryant, C.J.; Fokin, M.; Huege, J.; Fraser, K.; Jones, C.; Cao, M.; Faville, M.J.
Low pyrrolizidine alkaloid levels in perennial ryegrass is associated with the absence of a homospermidine synthase gene
BMC Plant Biol.
18
56
2018
Lolium perenne (A0A2R4PB59)
brenda
Kruse, L.H.; Stegemann, T.; Sievert, C.; Ober, D.
Identification of a second site of pyrrolizidine alkaloid biosynthesis in comfrey to boost plant defense in floral stage
Plant Physiol.
174
47-55
2017
Symphytum officinale (Q5ZN55)
brenda
Kruse, L.H.; Stegemann, T.; Jensen-Kroll, J.; Engelhardt, A.; Wesseling, A.M.; Lippert, A.; Ludwig-Mueller, J.; Ober, D.
Reduction of pyrrolizidine alkaloid levels in comfrey (Symphytum officinale) hairy roots by RNAi silencing of homospermidine synthase
Planta Med.
85
1177-1186
2019
Symphytum officinale (Q5ZN55)
brenda
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