L-phenylalanine catabolism in Rhodococcus qingshengii djl-6-2

Best path

aroP, ARO8, PPDCalpha, PPDCbeta, pad-dh, paaK, paaA, paaB, paaC, paaE, paaG, paaZ1, paaZ2, paaJ1, paaF, paaH, paaJ2

Rules

Overview: Phenylalanine utilization in GapMind is based on MetaCyc pathway L-phenylalanine degradation I (aerobic, via tyrosine, link), pathway II (anaerobic, via phenylacetaldehyde dehydrogenase, link), degradation via phenylpyruvate:ferredoxin oxidoreductase (PMC3346364), or degradation via phenylacetaldehyde:ferredoxin oxidoreductase (PMID:24214948). (MetaCyc describes additional pathways, but they do not result in carbon incorporation or are not reported in prokaryotes, so they are not included in GapMind.)

• all:
  • phenylalanine-transport, ARO8, phenylpyruvate-fd-oxidoreductase and phenylacetyl-CoA-degradation
  • or phenylalanine-transport, ARO8, phenylpyruvate-decarboxylase, pad-dh and phenylacetate-degradation
  • or phenylalanine-transport, ARO8, phenylpyruvate-decarboxylase, pfor and phenylacetate-degradation
  • or phenylalanine-transport, PAH, PCBD, QDPR and tyrosine-degradation
  • Comment: Phenylalanine can be catabolized via transaminase ARO8, which forms phenylpyruvate (also known as 3-phenyl-2-oxo-propanoate), and phenylpyruvate:ferredoxin oxidoreductase, which forms phenylacetyl-CoA. In the anaerobic pathway, the transaminase ARO8 forms phenylpyruvate, a carboxy-lyase forms phenylacetaldehyde, and a dehydrogenase (pad-dh) forms phenylacetate Or, in a variation on the anaerobic pathway, the phenylacetaldehyde is oxidized to phenylacetate by phenylacetaldehyde:ferredoxin oxidoreductase (pfor). In the aerobic pathway, PAH forms tyrosine and hydroxylates its tetrahydropterin co-substrate; the tetrahydropterin is regenerated by dehydratase PCBD and reductase QDPR.
• phenylpyruvate-fd-oxidoreductase:
  • iorA and iorB
  • or iorAB
  • Comment: This enzyme is usually known as indolepyruvate:ferredoxin oxidoreductase, but it acts on phenylpyruvate as well, forming phenylacetyl-CoA (PMID:8206994). Phenylpyruvate:ferredoxin oxidoreductase has both heterodimeric (iorA/iorB) and fused (iorAB) forms.
• phenylpyruvate-decarboxylase:
  • ARO10
  • or PPDCalpha and PPDCbeta
  • Comment: Phenylpyruvate can be decarboxylated to phenylacetaldehyde by the typical homomeric enzyme, or by a heterodimer reported in Streptomyces virginiae (see PMID:28719183)
• phenylacetyl-CoA-degradation:
  • paaA, paaB, paaC, paaE, paaG, paaZ1, paaZ2, paaJ1, paaF, paaH and paaJ2
  • or phenylacetyl-CoA-dehydrogenase, phenylglyoxylate-dehydrogenase and benzoyl-CoA-degradation
  • Comment: In the aerobic pathway, oxygen-dependent 1,2-epoxidase (PaaABCE) converts phenylacetyl-CoA to 1,2-epoxyphenylacetyl-CoA, which spontaenously rearranges to 2-(oxepinyl)acetyl-CoA; isomerase PaaG forms 2-oxepin-2(3H)-ylideneacetyl-CoA ("oxepin-CoA"); a ring-opening hydrolase forms 3-oxo-5,6-didehydrosuberyl-CoA semialdehyde; a dehydrogenase forms 3-oxo-5,6-didehydrosuberyl-CoA; thiolase PaaJ forms cis-3,4-didehydroadipyl-CoA (and acetyl-CoA); isomerase PaaG forms trans-2,3-didehydroadipyl-CoA; hydratase PaaF forms (3S)-hydroxyadipyl-CoA; dehydrogenase PaaH forms 3-oxoadipyl-CoA, and thiolase PaaJ forms succinyl-CoA and acetyl-CoA. (The role of PaaG is described in PMID:31689071 and differs slightly from MetaCyc.) In the anaerobic pathway, a dehydrogenase forms phenylglyoxyl-CoA, a hydrolase forms phenylglyoxylate (this step is not linked to sequence but is likely provided by the phenylglyoxylyl-CoA dehydrogenase, see PMID:10336636), and another dehydrogenase forms benzoyl-CoA and CO2. In principle, this pathway could occur aerobically, so GapMind includes aerobic pathways for degrading the benzoyl-CoA.
• phenylacetate-degradation: paaK and phenylacetyl-CoA-degradation
  • Comment: Phenylacetate is activated to phenylacetyl-CoA by paaK
• benzoyl-CoA-degradation:
  • benzoyl-CoA-reductase, dch, had, oah, pimB and glutaryl-CoA-degradation
  • or benzoyl-CoA-reductase, Ch1CoA, badK, badH, badI, pimD, pimC, pimF and glutaryl-CoA-degradation
  • or boxA, boxB, boxC, boxD, paaF, paaH and paaJ2
  • Comment: Benzoyl-CoA can be degraded anaerobically (link) by reduction to cyclohex-1,5-diene-1-carbonyl-CoA, followed by hydratase (dch) to 6-hydroxycyclohex-1-ene-1-carbonyl-CoA, a dehydrogenase to 6-oxocyclohex-1-ene-1-carbonyl-CoA, a hydrolase to 2-hydroxy-6-oxocycloheane-1-carbonyl-CoA, a ring-opening hydrolase to 3-hydroxypimeloyl-CoA [the last two steps are both catalyzed by oah], a dehydrogenase to 3-oxopimeloyl-CoA [not linked to sequence and omitted], and an acetyltransferase to glutaryl-CoA and acetyl-CoA. Alternatively, after reduction to cyclohex-1,5-diene-1-carbonyl-CoA, Ch1CoA can further reduce it to cyclohex-1-ene-1-carboxyl-CoA (link), followed by hydration to 2-hydroxy-cyclohexane-1-carbonyl-CoA, oxidation to 2-ketocyclohexane-1-carbonyl-CoA, cleavage by a ring-opening hydrolase to pimeloyl-CoA, oxidation to 2,3-didehydropimeloyl-CoA, hydration to 3-hydroxypimeloyl-C, oxidation to 3-oxopimeloyl-CoA and cleavage by a thiolase to glutaryl-CoA and acetyl-CoA. Benzoyl-CoA degradation can be degraded aerobically (link) by an epoxidase (boxAB) that forms 2,3-epoxy-2-3-dihydrobenzoyl-CoA; a dihydrolase forms cis-3,4-dihydroadipyl-CoA semialdehyde and formate; a dehydrogenase forms cis-3,4-dehydroadipyl-CoA; and an unknown isomerase forms trans-2,3-dehydroadipyl-CoA. This is converted to succinyl-CoA as in the anaerobic pathway (paaF, paaH, and paaJ2).
• phenylglyoxylate-dehydrogenase: padG, padI, padE, padF and padH
• phenylacetyl-CoA-dehydrogenase: padB, padC and padD
• glutaryl-CoA-degradation: gcdH, ech, fadB and atoB
  • Comment: In MetaCyc pathway glutaryl-CoA degradation (link), glutaryl-CoA is oxidized to (E)-glutaconyl-CoA and oxidatively decarboxylated to crotonyl-CoA (both by the same enzyme), hydrated to 3-hydroxybutanoyl-CoA, oxidized to acetoacetyl-CoA, and cleaved to two acetyl-CoA.
• benzoyl-CoA-reductase:
  • bcrA, bcrB, bcrC and bcrD
  • or bamB, bamC, bamD, bamE, bamF, bamG, bamH and bamI
  • Comment: Benzoyl-CoA reduction is energetically unfavorable. There are two classes of reductases: class I enzymes (bcrABCD) use ATP to drive the reaction, while class II enzymes (bamBCDEFGHI) are thought to us an electron bifurcation. SYN_02587 (Q2LQN9) from Syntrophus aciditrophicus, which can oxidize cyclohex-1,5-diene-1-carbonyl-CoA to benzoyl-CoA, is not included because it seems to lack a mechanism to drive benzoyl-CoA reduction.
• tyrosine-degradation: HPD, hmgA, maiA, fahA and acetoacetate-degradation
  • Comment: In pathway I, an aminotransferase (not represented) forms 3-(4-hydroxyphenyl)pyruvate, dioxygenase HPD forms homogentisate, another oxygenase forms 4-maleyl-acetoacetate, an isomerase forms 4-fumaryl-acetoacetate, and a hydrolase yields acetoacetate and fumarate. (Fumarate is part of the TCA cycle so its catabolism is not described.)
• acetoacetate-degradation: acetoacetate-activation and atoB
  • Comment: The acetoacetate is activated to acetoacetyl-CoA, and cleaved by acetyl-CoA acetyltransferase, giving two acetyl-CoA.
• acetoacetate-activation:
  • atoA and atoD
  • or aacS
  • Comment: acetyl-CoA:acetoacetyl-CoA transferase (sometimes given EC 2.8.3.9 or EC 2.8.3.8) or succinyl-CoA:acetoacetyl-CoA transferase (EC 2.8.3.5, also known as 3-oxoacid CoA-transferase) can activate acetoacetate. These have an A and B subunit. Alternatively, an ATP-dependent ligase (aacS) can activate acetoacetate (EC 6.2.1.16).
• phenylalanine-transport:
  • livF, livG, livH, livM and livJ
  • or aroP
  • Comment: Transporters were identified using query: transporter:phenylalanine:L-phenylalanine:phe

76 steps (47 with candidates)

Or see definitions of steps

Step	Description	Best candidate	2nd candidate
aroP	L-phenylalanine:H+ symporter AroP	C1M55_RS20600	C1M55_RS07700
ARO8	L-phenylalanine transaminase	C1M55_RS02065	C1M55_RS01535
PPDCalpha	phenylpyruvate decarboxylase, alpha subunit	C1M55_RS30500	C1M55_RS19770
PPDCbeta	phenylpyruvate decarboxylase, beta subunit	C1M55_RS30495	C1M55_RS19775
pad-dh	phenylacetaldehyde dehydrogenase	C1M55_RS09205	C1M55_RS09155
paaK	phenylacetate-CoA ligase	C1M55_RS27950	C1M55_RS08200
paaA	phenylacetyl-CoA 1,2-epoxidase, subunit A	C1M55_RS27975
paaB	phenylacetyl-CoA 1,2-epoxidase, subunit B	C1M55_RS27970
paaC	phenylacetyl-CoA 1,2-epoxidase, subunit C	C1M55_RS27965
paaE	phenylacetyl-CoA 1,2-epoxidase, subunit E	C1M55_RS27955	C1M55_RS08985
paaG	1,2-epoxyphenylacetyl-CoA isomerase / 2-(oxepinyl)acetyl-CoA isomerase / didehydroadipyl-CoA isomerase	C1M55_RS27980	C1M55_RS08860
paaZ1	oxepin-CoA hydrolase	C1M55_RS28000	C1M55_RS26225
paaZ2	3-oxo-5,6-didehydrosuberyl-CoA semialdehyde dehydrogenase	C1M55_RS28000
paaJ1	3-oxo-5,6-dehydrosuberyl-CoA thiolase	C1M55_RS26675	C1M55_RS04430
paaF	2,3-dehydroadipyl-CoA hydratase	C1M55_RS19610	C1M55_RS12340
paaH	3-hydroxyadipyl-CoA dehydrogenase	C1M55_RS07980	C1M55_RS25285
paaJ2	3-oxoadipyl-CoA thiolase	C1M55_RS26675	C1M55_RS04430
Alternative steps:
aacS	acetoacetyl-CoA synthetase	C1M55_RS09195	C1M55_RS04410
ARO10	phenylpyruvate decarboxylase
atoA	acetoacetyl-CoA transferase, A subunit	C1M55_RS09285	C1M55_RS26645
atoB	acetyl-CoA C-acetyltransferase	C1M55_RS28700	C1M55_RS07210
atoD	acetoacetyl-CoA transferase, B subunit	C1M55_RS26640	C1M55_RS09290
badH	2-hydroxy-cyclohexanecarboxyl-CoA dehydrogenase	C1M55_RS27655	C1M55_RS30565
badI	2-ketocyclohexanecarboxyl-CoA hydrolase	C1M55_RS08580	C1M55_RS19610
badK	cyclohex-1-ene-1-carboxyl-CoA hydratase	C1M55_RS19610	C1M55_RS20280
bamB	class II benzoyl-CoA reductase, BamB subunit
bamC	class II benzoyl-CoA reductase, BamC subunit
bamD	class II benzoyl-CoA reductase, BamD subunit	C1M55_RS06770
bamE	class II benzoyl-CoA reductase, BamE subunit
bamF	class II benzoyl-CoA reductase, BamF subunit
bamG	class II benzoyl-CoA reductase, BamG subunit
bamH	class II benzoyl-CoA reductase, BamH subunit	C1M55_RS13750
bamI	class II benzoyl-CoA reductase, BamI subunit
bcrA	ATP-dependent benzoyl-CoA reductase, alpha subunit
bcrB	ATP-dependent benzoyl-CoA reductase, beta subunit
bcrC	ATP-dependent benzoyl-CoA reductase, gamma subunit
bcrD	ATP-dependent benzoyl-CoA reductase, delta subunit
boxA	benzoyl-CoA epoxidase, subunit A
boxB	benzoyl-CoA epoxidase, subunit B
boxC	2,3-epoxybenzoyl-CoA dihydrolase
boxD	3,4-dehydroadipyl-CoA semialdehyde dehydrogenase	C1M55_RS28000
Ch1CoA	cyclohex-1-ene-1-carbonyl-CoA dehydrogenase	C1M55_RS25280	C1M55_RS19625
dch	cyclohexa-1,5-diene-1-carboxyl-CoA hydratase	C1M55_RS19610	C1M55_RS01960
ech	(S)-3-hydroxybutanoyl-CoA hydro-lyase	C1M55_RS19610	C1M55_RS12340
fadB	(S)-3-hydroxybutanoyl-CoA dehydrogenase	C1M55_RS07980	C1M55_RS25285
fahA	fumarylacetoacetate hydrolase	C1M55_RS23760	C1M55_RS12530
gcdH	glutaryl-CoA dehydrogenase	C1M55_RS24690	C1M55_RS09530
had	6-hydroxycyclohex-1-ene-1-carbonyl-CoA dehydrogenase	C1M55_RS27575
hmgA	homogentisate dioxygenase	C1M55_RS23750
HPD	4-hydroxyphenylpyruvate dioxygenase	C1M55_RS25575
iorA	phenylpyruvate:ferredoxin oxidoreductase, IorA subunit
iorAB	phenylpyruvate:ferredoxin oxidoreductase, fused IorA/IorB	C1M55_RS23815
iorB	phenylpyruvate:ferredoxin oxidoreductase, IorB subunit
livF	L-phenylalanine ABC transporter, ATPase component 1 (LivF)	C1M55_RS08565	C1M55_RS16615
livG	L-phenylalanine ABC transporter, ATPase component 2 (LivG)	C1M55_RS22600	C1M55_RS16610
livH	L-phenylalanine ABC transporter, permease component 1 (LivH)	C1M55_RS22590	C1M55_RS06865
livJ	L-phenylalanine ABC transporter, substrate-binding component LivJ/LivK
livM	L-phenylalanine ABC transporter, permease component 2 (LivM)	C1M55_RS22585	C1M55_RS16605
maiA	maleylacetoacetate isomerase
oah	6-oxocyclohex-1-ene-1-carbonyl-CoA hydratase
padB	phenylacetyl-CoA dehydrogenase, PadB subunit
padC	phenylacetyl-CoA dehydrogenase, PadC subunit
padD	phenylacetyl-CoA dehydrogenase, PadD subunit
padE	phenylglyoxylate dehydrogenase, gamma subunit
padF	phenylglyoxylate dehydrogenase, delta subunit
padG	phenylglyoxylate dehydrogenase, alpha subunit
padH	phenylglyoxylate dehydrogenase, epsilon subunit
padI	phenylglyoxylate dehydrogenase, beta subunit
PAH	phenylalanine 4-monooxygenase
PCBD	pterin-4-alpha-carbinoalamine dehydratase	C1M55_RS20700
pfor	phenylacetaldeyde:ferredoxin oxidoreductase
pimB	3-oxopimeloyl-CoA:CoA acetyltransferase	C1M55_RS27635	C1M55_RS21060
pimC	pimeloyl-CoA dehydrogenase, small subunit	C1M55_RS20160	C1M55_RS25340
pimD	pimeloyl-CoA dehydrogenase, large subunit	C1M55_RS20165	C1M55_RS25345
pimF	6-carboxyhex-2-enoyl-CoA hydratase	C1M55_RS14320
QDPR	6,7-dihydropteridine reductase	C1M55_RS27940

Confidence: high confidence medium confidence low confidence
transporter – transporters and PTS systems are shaded because predicting their specificity is particularly challenging.

This GapMind analysis is from Sep 24 2021. The underlying query database was built on Sep 17 2021.