Record Information
Version 1.0
Update Date 1/22/2018 12:54:54 PM
Metabolite IDPAMDB000152
Identification
Name: L-Cysteine
Description:Cysteine is a naturally occurring, sulfur-containing amino acid that is found in most proteins, although only in small quantities. Cysteine is unique amongst the twenty natural amino acids as it contains a thiol group. Thiol groups can undergo oxidation/reduction (redox) reactions; when cysteine is oxidized it can form cystine, which is two cysteine residues joined by a disulfide bond. This reaction is reversible: as reduction of this disulphide bond regenerates two cysteine molecules. The disulphide bonds of cystine are crucial to defining the structures of many proteins. Cysteine is often involved in electron-transfer reactions, and help the enzyme catalyze its reaction. Cysteine is also part of the antioxidant glutathione. Oxidation of cysteine can produce a disulfide bond with another thiol, or further oxidation can produce sulphfinic or sulfonic acids. The cysteine thiol group is also a nucleophile and can undergo addition and substitution reactions. Thiol groups become much more reactive when they are ionized, and cysteine residues in proteins have pKa values close to neutrality, so are often in their reactive thiolate form in the cell. The thiol group also has a high affinity for heavy metals and proteins containing cysteine will bind metals such as mercury, lead and cadmium tightly.Due to this ability to undergo redox reactions, cysteine has antioxidant properties. Cysteine is important in energy metabolism. (http://www.dcnutrition.com/AminoAcids/)
Structure
Thumb
Synonyms:
  • (+)-2-Amino-3-mercaptopropionate
  • (+)-2-Amino-3-mercaptopropionic acid
  • (2R)-2-amino-3-mercaptopropanoate
  • (2R)-2-amino-3-mercaptopropanoic acid
  • (2R)-2-amino-3-sulfanylpropanoate
  • (2R)-2-amino-3-sulfanylpropanoic acid
  • (2R)-2-amino-3-sulphanylpropanoate
  • (2R)-2-amino-3-sulphanylpropanoic acid
  • (R)-(+)-cysteine
  • (R)-2-amino-3-mercapto-Propanoate
  • (R)-2-amino-3-mercapto-Propanoic acid
  • (R)-2-Amino-3-mercaptopropanoate
  • (R)-2-Amino-3-mercaptopropanoic acid
  • (R)-cysteine
  • 2-Amino-3-mercaptopropanoate
  • 2-Amino-3-mercaptopropanoic acid
  • 2-Amino-3-mercaptopropionate
  • 2-Amino-3-mercaptopropionic acid
  • 3-Mercapto-L-Alanine
  • a-amino-b-Thiolpropionate
  • a-amino-b-Thiolpropionic acid
  • Acetylcysteine
  • Alpha-Amino-beta-thiolpropionate
  • Alpha-Amino-beta-thiolpropionic acid
  • B-Mercaptoalanine
  • Beta-Mercaptoalanine
  • C
  • Carbocysteine
  • Cisteina
  • Cisteinum
  • Cys
  • Cystein
  • Cysteine
  • Cysteinum
  • Free cysteine
  • Half-cystine
  • L Cysteine
  • L-(+)-Cysteine
  • L-2-Amino-3-mercaptopropanoate
  • L-2-Amino-3-mercaptopropanoic acid
  • L-2-Amino-3-mercaptopropionate
  • L-2-Amino-3-mercaptopropionic acid
  • L-Cystein
  • L-Cysteine
  • Polycysteine
  • Thioserine
  • α-amino-β-Thiolpropionate
  • α-amino-β-Thiolpropionic acid
  • β-Mercaptoalanine
Chemical Formula: C3H7NO2S
Average Molecular Weight: 121.158
Monoisotopic Molecular Weight: 121.019749163
InChI Key: XUJNEKJLAYXESH-REOHCLBHSA-N
InChI:InChI=1S/C3H7NO2S/c4-2(1-7)3(5)6/h2,7H,1,4H2,(H,5,6)/t2-/m0/s1
CAS number: 52-90-4
IUPAC Name:(2R)-2-amino-3-sulfanylpropanoic acid
Traditional IUPAC Name: L-cysteine
SMILES:N[C@@H](CS)C(O)=O
Chemical Taxonomy
Taxonomy DescriptionThis compound belongs to the class of organic compounds known as l-alpha-amino acids. These are alpha amino acids which have the L-configuration of the alpha-carbon atom.
Kingdom Organic compounds
Super ClassOrganic acids and derivatives
Class Carboxylic acids and derivatives
Sub ClassAmino acids, peptides, and analogues
Direct Parent L-alpha-amino acids
Alternative Parents
Substituents
  • L-alpha-amino acid
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Alkylthiol
  • Hydrocarbon derivative
  • Primary amine
  • Organosulfur compound
  • Organooxygen compound
  • Organonitrogen compound
  • Primary aliphatic amine
  • Carbonyl group
  • Amine
  • Aliphatic acyclic compound
Molecular Framework Aliphatic acyclic compounds
External Descriptors
Physical Properties
State: Solid
Charge:0
Melting point: 220 °C
Experimental Properties:
PropertyValueSource
Water Solubility:277 mg/mL at 25 oC [BEILSTEIN]; 277.0 mg/mL [BEILSTEIN]PhysProp
LogP:-2.49 [HANSCH,C ET AL. (1995)]PhysProp
Predicted Properties
PropertyValueSource
Water Solubility23.1 mg/mLALOGPS
logP-2.6ALOGPS
logP-2.8ChemAxon
logS-0.72ALOGPS
pKa (Strongest Acidic)2.35ChemAxon
pKa (Strongest Basic)9.05ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count3ChemAxon
Polar Surface Area63.32 Å2ChemAxon
Rotatable Bond Count2ChemAxon
Refractivity28.22 m3·mol-1ChemAxon
Polarizability11.41 Å3ChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Biological Properties
Cellular Locations: Cytoplasm
Reactions:
Cysteinylglycine + Water > L-Cysteine + Glycine
Adenosine triphosphate + L-Cysteine + Water > ADP + Hydrogen ion + Phosphate + L-Cysteine
Adenosine triphosphate + L-Cysteine + Water > ADP + Hydrogen ion + Phosphate + L-Cysteine
L-Cysteine + SufSE sulfur acceptor complex > L-Alanine + SufSE with bound sulfur
O-Acetylserine + Hydrogen sulfide <> Acetic acid + L-Cysteine + Hydrogen ion
L-Cysteine + Water > Hydrogen sulfide + Ammonium + Pyruvic acid
Adenosine triphosphate + L-Cysteine + tRNA(Cys) + tRNA(Cys) <> Adenosine monophosphate + L-Cysteinyl-tRNA(Cys) + Pyrophosphate + L-Cysteinyl-tRNA(Cys)
L-Cysteine + IscS sulfur acceptor protein > L-Alanine + IscS with bound sulfur
Adenosine triphosphate + L-Cysteine + L-Glutamate <> ADP + gamma-Glutamylcysteine + Hydrogen ion + Phosphate
D-4'-Phosphopantothenate + Cytidine triphosphate + L-Cysteine > 4-Phosphopantothenoylcysteine + Cytidine monophosphate + Hydrogen ion + Pyrophosphate
L-Cysteine + O-Succinyl-L-homoserine <> L-Cystathionine + Hydrogen ion + Succinic acid
L-Cysteine + Water <> Hydrogen sulfide + Pyruvic acid + Ammonia
Adenosine triphosphate + L-Glutamate + L-Cysteine <> ADP + Phosphate + gamma-Glutamylcysteine
O-Acetylserine + Hydrogen sulfide <> L-Cysteine + Acetic acid
Cystathionine + Succinic acid <> O-Succinyl-L-homoserine + L-Cysteine
O-Succinyl-L-homoserine + L-Cysteine <> L-Cystathionine + Succinic acid
Adenosine triphosphate + L-Cysteine + tRNA(Cys) <> Adenosine monophosphate + Pyrophosphate + L-Cysteinyl-tRNA(Cys)
Adenosine triphosphate + D-4'-Phosphopantothenate + L-Cysteine <> Adenosine monophosphate + Pyrophosphate + 4-Phosphopantothenoylcysteine
Cytidine triphosphate + D-4'-Phosphopantothenate + L-Cysteine <> Cytidine monophosphate + Pyrophosphate + 4-Phosphopantothenoylcysteine
O-Acetylserine + Thiosulfate + Thioredoxin + Hydrogen ion <> L-Cysteine + Sulfite + Thioredoxin disulfide + Acetic acid
[Enzyme]-cysteine + L-Cysteine <> [Enzyme]-S-sulfanylcysteine + L-Alanine

Pathways:
Spectra
Spectra:
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (4 TMS)splash10-00kb-0950000000-df7e91c95b610ff21c79View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (4 TMS)splash10-00kb-0940000000-aefe34765fb447090a23View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (4 TMS)splash10-00kb-0970000000-10a155c40ea499023052View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies)splash10-00kb-0940000000-037a3a34651c3154b3b3View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (4 TMS)splash10-00di-9850000000-118c43e33861a6baa8d2View in MoNA
GC-MSGC-MS Spectrum - GC-MSNot Available
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-00b9-9600000000-374c5872d68662832769View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-0a4i-9000000000-ddbd3df6b8dbb280ffbaView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-0a4i-9000000000-320a2c77443b80ebf733View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0089-0900000000-9dcd3d757c5cd11eb18eView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0udi-3900000000-212e081fe83ad70de0adView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-000i-9000000000-2eb01f41c225f614db24View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-001i-0900000000-a19834eb7cb9f211fdf2View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-00di-0900000000-2458f2587761e779ed93View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0a4i-9000000000-77e590f0ed26f69b31c0View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0udi-3900000000-7b1857997392b006b95fView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT (LTQ Orbitrap XL, Thermo Scientfic) , Positivesplash10-0a4i-3900000000-bc268c27ed5706a4bbd2View in MoNA
LC-MS/MSLC-MS/MS Spectrum - CE-ESI-TOF (CE-system connected to 6210 Time-of-Flight MS, Agilent) , Positivesplash10-00di-0900000000-4573390bccc238e3c91bView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, PositiveNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, NegativeNot Available
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, NegativeNot Available
1D NMR13C NMR SpectrumNot Available
1D NMR1H NMR SpectrumNot Available
1D NMR1H NMR SpectrumNot Available
2D NMR[1H,1H] 2D NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
References
References:
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  • Kozaki K, Miyaishi O, Asai N, Iida K, Sakata K, Hayashi M, Nishida T, Matsuyama M, Shimizu S, Kaneda T, et al.: Tissue distribution of ERp61 and association of its increased expression with IgG production in hybridoma cells. Exp Cell Res. 1994 Aug;213(2):348-58. Pubmed: 8050492
  • Li Y, Gamper N, Shapiro MS: Single-channel analysis of KCNQ K+ channels reveals the mechanism of augmentation by a cysteine-modifying reagent. J Neurosci. 2004 Jun 2;24(22):5079-90. Pubmed: 15175377
  • Lindzen M, Gottschalk KE, Fuzesi M, Garty H, Karlish SJ: Structural interactions between FXYD proteins and Na+,K+-ATPase: alpha/beta/FXYD subunit stoichiometry and cross-linking. J Biol Chem. 2006 Mar 3;281(9):5947-55. Epub 2005 Dec 21. Pubmed: 16373350
  • Naisbitt DJ, Vilar FJ, Stalford AC, Wilkins EG, Pirmohamed M, Park BK: Plasma cysteine deficiency and decreased reduction of nitrososulfamethoxazole with HIV infection. AIDS Res Hum Retroviruses. 2000 Dec 10;16(18):1929-38. Pubmed: 11153075
  • Nicholson JK, O'Flynn MP, Sadler PJ, Macleod AF, Juul SM, Sonksen PH: Proton-nuclear-magnetic-resonance studies of serum, plasma and urine from fasting normal and diabetic subjects. Biochem J. 1984 Jan 15;217(2):365-75. Pubmed: 6696735
  • Nishiya Y, Yoshida Y, Yoshimura M, Fukamachi H, Nakano Y: Homogeneous enzymatic assay for L-cysteine with betaC-S lyase. Biosci Biotechnol Biochem. 2005 Nov;69(11):2244-6. Pubmed: 16306712
  • Norris FA, Wilson MP, Wallis TS, Galyov EE, Majerus PW: SopB, a protein required for virulence of Salmonella dublin, is an inositol phosphate phosphatase. Proc Natl Acad Sci U S A. 1998 Nov 24;95(24):14057-9. Pubmed: 9826652
  • Paivalainen S, Suokas M, Lahti O, Heape AM: Degraded myelin-associated glycoprotein (dMAG) formation from pure human brain myelin-associated glycoprotein (MAG) is not mediated by calpain or cathepsin L-like activities. J Neurochem. 2003 Feb;84(3):533-45. Pubmed: 12558973
  • Sandmann J, Schwedhelm KS, Tsikas D: Specific transport of S-nitrosocysteine in human red blood cells: Implications for formation of S-nitrosothiols and transport of NO bioactivity within the vasculature. FEBS Lett. 2005 Aug 1;579(19):4119-24. Pubmed: 16023102
  • Santamaria I, Velasco G, Cazorla M, Fueyo A, Campo E, Lopez-Otin C: Cathepsin L2, a novel human cysteine proteinase produced by breast and colorectal carcinomas. Cancer Res. 1998 Apr 15;58(8):1624-30. Pubmed: 9563472
  • Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. Pubmed: 19212411
  • Taveau M, Bourg N, Sillon G, Roudaut C, Bartoli M, Richard I: Calpain 3 is activated through autolysis within the active site and lyses sarcomeric and sarcolemmal components. Mol Cell Biol. 2003 Dec;23(24):9127-35. Pubmed: 14645524
  • van der Werf, M. J., Overkamp, K. M., Muilwijk, B., Coulier, L., Hankemeier, T. (2007). "Microbial metabolomics: toward a platform with full metabolome coverage." Anal Biochem 370:17-25. Pubmed: 17765195
  • Vijayendran, C., Barsch, A., Friehs, K., Niehaus, K., Becker, A., Flaschel, E. (2008). "Perceiving molecular evolution processes in Escherichia coli by comprehensive metabolite and gene expression profiling." Genome Biol 9:R72. Pubmed: 18402659
  • Winder, C. L., Dunn, W. B., Schuler, S., Broadhurst, D., Jarvis, R., Stephens, G. M., Goodacre, R. (2008). "Global metabolic profiling of Escherichia coli cultures: an evaluation of methods for quenching and extraction of intracellular metabolites." Anal Chem 80:2939-2948. Pubmed: 18331064
  • Yu FH, Westenbroek RE, Silos-Santiago I, McCormick KA, Lawson D, Ge P, Ferriera H, Lilly J, DiStefano PS, Catterall WA, Scheuer T, Curtis R: Sodium channel beta4, a new disulfide-linked auxiliary subunit with similarity to beta2. J Neurosci. 2003 Aug 20;23(20):7577-85. Pubmed: 12930796
  • Zhang JT, Li QX, Wang D, Zhu ZL, Yang YH, Cui DS, Wang MW, Sun XF: Up-regulation of PINCH in the stroma of oral squamous cell carcinoma predicts nodal metastasis. Oncol Rep. 2005 Dec;14(6):1519-22. Pubmed: 16273248
Synthesis Reference: Kumagai, Hidehiko; Tanaka, Hideyuki; Sejima, Shunsuke; Yamada, Hideaki. Elimination and replacement reactions of b-chloro-L-alanine by cysteine desulfhydrase from Aerobacter aerogenes. Agricultural and Biological Chemistry (1977), 41(10), 2071-5.
Material Safety Data Sheet (MSDS) Download (PDF)
External Links:
ResourceLink
CHEBI ID17561
HMDB IDHMDB00574
Pubchem Compound ID5862
Kegg IDC00097
ChemSpider ID5653
WikipediaL-Cysteine
BioCyc IDCYS
EcoCyc IDCYS
Ligand ExpoFCY

Enzymes

General function:
Involved in proteolysis
Specific function:
Aminopeptidase N is involved in the degradation of intracellular peptides generated by protein breakdown during normal growth as well as in response to nutrient starvation
Gene Name:
pepN
Locus Tag:
PA3083
Molecular weight:
100 kDa
Reactions
Release of an N-terminal amino acid, Xaa-|-Yaa- from a peptide, amide or arylamide. Xaa is preferably Ala, but may be most amino acids including Pro (slow action). When a terminal hydrophobic residue is followed by a prolyl residue, the two may be released as an intact Xaa-Pro dipeptide.
General function:
Involved in metabolic process
Specific function:
Catalyzes the removal of elemental sulfur and selenium atoms from cysteine and selenocysteine to produce alanine. Functions as a sulfur delivery protein for NAD, biotin and Fe-S cluster synthesis. Transfers sulfur on 'Cys-456' of thiI in a transpersulfidation reaction. Transfers sulfur on 'Cys-19' of tusA in a transpersulfidation reaction. Functions also as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate
Gene Name:
iscS
Locus Tag:
PA3814
Molecular weight:
44.7 kDa
Reactions
L-cysteine + acceptor = L-alanine + S-sulfanyl-acceptor.
General function:
Involved in glutamate-cysteine ligase activity
Specific function:
ATP + L-glutamate + L-cysteine = ADP + phosphate + gamma-L-glutamyl-L-cysteine
Gene Name:
gshA
Locus Tag:
PA5203
Molecular weight:
59.2 kDa
Reactions
ATP + L-glutamate + L-cysteine = ADP + phosphate + gamma-L-glutamyl-L-cysteine.
General function:
Involved in cysteine biosynthetic process from serine
Specific function:
O(3)-acetyl-L-serine + H(2)S = L-cysteine + acetate
Gene Name:
cysK
Locus Tag:
PA2709
Molecular weight:
34.3 kDa
Reactions
O(3)-acetyl-L-serine + H(2)S = L-cysteine + acetate.
3-chloro-L-alanine + thioglycolate = S-carboxymethyl-L-cysteine + chloride.
General function:
Involved in phosphopantothenate--cysteine ligase activity
Specific function:
Catalyzes two steps in the biosynthesis of coenzyme A. In the first step cysteine is conjugated to 4'-phosphopantothenate to form 4-phosphopantothenoylcysteine, in the latter compound is decarboxylated to form 4'-phosphopantotheine
Gene Name:
coaBC
Locus Tag:
PA5320
Molecular weight:
43.1 kDa
Reactions
N-((R)-4'-phosphopantothenoyl)-L-cysteine = pantotheine 4'-phosphate + CO(2).
CTP + (R)-4'-phosphopantothenate + L-cysteine = CMP + diphosphate + N-((R)-4'-phosphopantothenoyl)-L-cysteine.
General function:
Involved in cysteine biosynthetic process from serine
Specific function:
Two cysteine synthase enzymes are found. Both catalyze the same reaction. Cysteine synthase B can also use thiosulfate in place of sulfide to give cysteine thiosulfonate as a product
Gene Name:
cysM
Locus Tag:
PA0932
Molecular weight:
32.4 kDa
Reactions
O(3)-acetyl-L-serine + H(2)S = L-cysteine + acetate.
General function:
Involved in cysteine-tRNA ligase activity
Specific function:
ATP + L-cysteine + tRNA(Cys) = AMP + diphosphate + L-cysteinyl-tRNA(Cys)
Gene Name:
cysS
Locus Tag:
PA1795
Molecular weight:
51.2 kDa
Reactions
ATP + L-cysteine + tRNA(Cys) = AMP + diphosphate + L-cysteinyl-tRNA(Cys).
General function:
Involved in aminopeptidase activity
Specific function:
Presumably involved in the processing and regular turnover of intracellular proteins. Catalyzes the removal of unsubstituted N-terminal amino acids from various peptides. Required for plasmid ColE1 site-specific recombination but not in its aminopeptidase activity. Could act as a structural component of the putative nucleoprotein complex in which the Xer recombination reaction takes place
Gene Name:
pepA
Locus Tag:
PA3831
Molecular weight:
52.3 kDa
Reactions
Release of an N-terminal amino acid, Xaa-|-Yaa-, in which Xaa is preferably Leu, but may be other amino acids including Pro although not Arg or Lys, and Yaa may be Pro. Amino acid amides and methyl esters are also readily hydrolyzed, but rates on arylamides are exceedingly low.
Release of an N-terminal amino acid, preferentially leucine, but not glutamic or aspartic acids.
General function:
Involved in RNA binding
Specific function:
Catalyzes the ATP-dependent transfer of a sulfur to tRNA to produce 4-thiouridine in position 8 of tRNAs, which functions as a near-UV photosensor. Also catalyzes the transfer of sulfur to the sulfur carrier protein ThiS, forming ThiS-thiocarboxylate. This is a step in the synthesis of thiazole, in the thiamine biosynthesis pathway. The sulfur is donated as persulfide by iscS
Gene Name:
thiI
Locus Tag:
PA5118
Molecular weight:
54.8 kDa
Reactions
L-cysteine + 'activated' tRNA = L-serine + tRNA containing a thionucleotide.
[IscS]-SSH + [ThiS]-COAMP = [IscS]-SH + [ThiS]-COSH + AMP.

Transporters

General function:
Involved in proteolysis
Specific function:
Aminopeptidase N is involved in the degradation of intracellular peptides generated by protein breakdown during normal growth as well as in response to nutrient starvation
Gene Name:
pepN
Locus Tag:
PA3083
Molecular weight:
100 kDa
Reactions
Release of an N-terminal amino acid, Xaa-|-Yaa- from a peptide, amide or arylamide. Xaa is preferably Ala, but may be most amino acids including Pro (slow action). When a terminal hydrophobic residue is followed by a prolyl residue, the two may be released as an intact Xaa-Pro dipeptide.
General function:
Involved in nucleotide binding
Specific function:
Probably part of a binding-protein-dependent transport system yecCS for an amino acid. Probably responsible for energy coupling to the transport system
Gene Name:
yecC
Locus Tag:
PA5152
Molecular weight:
28.4 kDa