Reviewed, UniProtKB/Swiss-Prot Q8L1B1 (SYI2_PSEFL)

Names and origin

Protein names

Recommended name:
    Isoleucyl-tRNA synthetase 2
    EC=6.1.1.5
Alternative name(s):
    Isoleucine--tRNA ligase 2
      Short name=IleRS 2
    IleRS-R2

Gene names

Name:	ileS2
Synonyms:	mupM

Organism

Pseudomonas fluorescens

Taxonomic identifier

294 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Pseudomonadales › Pseudomonadaceae › Pseudomonas

Protein attributes

Sequence length	1030 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Catalyzes the attachment of isoleucine to tRNA(Ile). As IleRS can inadvertently accommodate and process structurally similar amino acids such as valine, to avoid such errors it has two additional distinct tRNA(Ile)-dependent editing activities. One activity is designated as 'pretransfer' editing and involves the hydrolysis of activated Val-AMP. The other activity is designated 'posttransfer' editing and involves deacylation of mischarged Val-tRNA(Ile) By similarity. HAMAP MF_02003 Confers high-level resistance to the antibiotic mupirocin (pseudomonic acid A), an Ile-analog produced by P.fluorescens NCIMB 10586 itself that competitively inhibits activation by Ile-tRNA synthetase, thus inhibiting protein biosynthesis. HAMAP MF_02003
Catalytic activity	ATP + L-isoleucine + tRNA(Ile) = AMP + diphosphate + L-isoleucyl-tRNA(Ile). HAMAP MF_02003
Cofactor	Zinc By similarity. HAMAP MF_02003
Subunit structure	Monomer By similarity. HAMAP MF_02003
Subcellular location	Cytoplasm By similarity HAMAP MF_02003.
Domain	IleRS has two distinct active sites: one for aminoacylation and one for editing. The misactivated valine is translocated from the active site to the editing site, which sterically excludes the correctly activated isoleucine. The single editing site contains two valyl binding pockets, one specific for each substrate (Val-AMP or Val-tRNA(Ile)) By similarity. HAMAP MF_02003
Miscellaneous	P.fluorescens NCIMB 10586 possesses two distinct IleRSs (IleRS-R1 and IleRS-R2), each with a different level of sensitivity to mupirocin. Purified IleRs-R2 shows no sensitivity to mupirocin even at a concentration of 5 mM, 100'000 fold higher than the Ki value of IleRS-R1. HAMAP MF_02003
Sequence similarities	Belongs to the class-I aminoacyl-tRNA synthetase family. IleS type 2 subfamily.
Biophysicochemical properties	Kinetic parameters: KM=10 µM for isoleucine HAMAP MF_02003 KM=330 µM for ATP

Ontologies

Keywords
Biological process	Antibiotic resistance Protein biosynthesis
Cellular component	Cytoplasm
Ligand	ATP-binding Metal-binding Nucleotide-binding Zinc
Molecular function	Aminoacyl-tRNA synthetase Ligase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	isoleucyl-tRNA aminoacylation Inferred from electronic annotation. Source: HAMAP response to antibiotic Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	ATP binding Inferred from electronic annotation. Source: HAMAP isoleucine-tRNA ligase activity Inferred from electronic annotation. Source: HAMAP zinc ion binding Inferred from electronic annotation. Source: HAMAP
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.3
	Chain	2 – 1030	1029	Isoleucyl-tRNA synthetase 2 HAMAP MF_02003		PRO_0000098556
Regions
	Motif	48 – 58	11	"HIGH" region HAMAP MF_02003
	Motif	589 – 593	5	"KMSKS" region HAMAP MF_02003
Sites
	Binding site	592	1	ATP By similarity
Experimental info
	Sequence conflict	175	1	G → R in AAL85500. Ref.1
	Sequence conflict	400	1	A → T in AAM12927. Ref.2
	Sequence conflict	667	1	L → P in AAM12927. Ref.2
	Sequence conflict	671	1	L → P in AAM12927. Ref.2
	Sequence conflict	717	1	Y → H in AAM12927. Ref.2
	Sequence conflict	805	1	R → C in AAM12927. Ref.2
	Sequence conflict	886	1	A → V in AAM12927. Ref.2
	Sequence conflict	939	1	S → P in AAM12927. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	Q8L1B1-1 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: 2D930693BE1DC935	FASTA	1,030	117,875
	10 20 30 40 50 60 MSTEGSGPVR FPAMEDAVLE RWEKEKTFEQ SISAREGKPV YVFYDGPPFA TGLPHYGHIL 70 80 90 100 110 120 TSYIKDVIPR YQTMLGKQVP RRWGWDCHGL PVEFEVEKAM GFKSKRDILE FGVEQFNDEC 130 140 150 160 170 180 RELVLKYADD WRGFVNRMGR WVDFDGAYKT MDNDYMESVL WGFKTLHDKG HVYEGGKIVP 190 200 210 220 230 240 YCVRCQTVLS NFEARLDDAF RPRRDMSAYV KFRQQDRPDT FFLAWTTTPW TLPANVALAV 250 260 270 280 290 300 AADENYVCIE HGEERLWLAE GCLGGLFDEP VILERCTGAE LAGLRYLPVV GEVIDASAHR 310 320 330 340 350 360 VVTADFVQMG DGSGIVHIAP AFGEDDALLG QQYELPAPNP VRDDGTFSDA VAQYAGQNIF 370 380 390 400 410 420 EATPRILADL KSSGLLFKQE QIEHNYPHCW RCDNPLIYRA VESWFIRASA LREQLVENNS 430 440 450 460 470 480 QVNWVPEHVK EGRFGDWIRN ARDWAVSRNR FWGAPIPVWR CDQCGTVEVM GSIAQIEARS 490 500 510 520 530 540 GRKVEDLHVP HIDEHRFACQ CCEGTMSRVT GVFDCWFESG AMPFASRHYP FENKQEFEQT 550 560 570 580 590 600 FPADFIVEYL AQTRGWFYTM MVISTGCFEQ NPFKNAMCHG VILAKDGRKM SKRLKNYPNP 610 620 630 640 650 660 MDLMQTHGSD ALRVALLASP VCKGEDIKFS EESVRDVVRR YHLLFWNCLQ FYKTFTEIDQ 670 680 690 700 710 720 FSPSGDLGQP LDNVLDHYLL HELAALESDI KMWMESLDFS KIYSRIEVFI NVLSTWYLRL 730 740 750 760 770 780 NKARIWRDGL DDDKRQCYEV LHYALSNFAR LLAPFMPFLA EAVYTELGYA DSVHLQDWPS 790 800 810 820 830 840 IDRQYLSYEL ADEMSSLRNL IASVRNVRET NGVSQKFPLR SIRVAGIEQA VLERYAQFLE 850 860 870 880 890 900 EELNVKQVQW AADADEWAQP VVVLIFSLLG KRLGPAMKAV TTAVKAGEYV IDEQGGLVAA 910 920 930 940 950 960 GQTIQPHEFE RRLTVRDTLN NVGIVENMVV WLDLDIDASL KREGAVRELN RRLQDLRKKA 970 980 990 1000 1010 1020 KLGYTEKVDI AVLGGAYVDE ILVHHEDWLK SQLLVQSLLR SDLEAPLAVD EVELPEGDPV 1030 RIQLRRSVLA

References

[1]	"Analysis of rILERS, an isoleucyl-tRNA synthetase gene associated with mupirocin production by Pseudomonas fluorescens NCIMB 10586." Rangaswamy V., Hernandez-Guzman G., Shufran K.A., Bender C.L. DNA Seq. 13:343-351(2002) [PubMed: 12652905] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: ATCC 49323 / NCIMB 10586.
[2]	"Nucleotide sequence of a 75 kb region of the chromosome of Pseudomonas fluorescens NCIMB 10586 required for biosynthesis of the polyketide antibiotic mupirocin." El-Sayed A.K., Hothersall J., Cooper S.M., Stephens E., Thomas C.M. Submitted (JAN-2002) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: ATCC 49323 / NCIMB 10586.
[3]	"How does Pseudomonas fluorescens avoid suicide from its antibiotic pseudomonic acid? Evidence for two evolutionarily distinct isoleucyl-tRNA synthetases conferring self-defense." Yanagisawa T., Kawakami M. J. Biol. Chem. 278:25887-25894(2003) [PubMed: 12672810] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 2-13, RESISTANCE TO MUPIROCIN. Strain: ATCC 49323 / NCIMB 10586.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AY079084 Genomic DNA. Translation: AAL85500.1. AF318063 Genomic DNA. Translation: AAM12927.1. AB062785 Genomic DNA. Translation: BAC07171.1.
3D structure databases
SMR	Q8L1B1. Positions 6-813, 10-855.
ModBase	Search...
Enzyme and pathway databases
BRENDA	6.1.1.5. 329.
Family and domain databases
HAMAP	MF_02003. Ile_tRNA_synth_type2. [Tree]
InterPro	IPR001412. aa-tRNA-synth_I_CS. IPR002300. aa-tRNA-synth_Ia. IPR002301. Ile-tRNA-synt_Ia. IPR015905. Ile-tRNA-synt_Ia_N. IPR018353. Isoleucyl-tRNA_synthetase. IPR014729. Rossmann-like_a/b/a_fold. IPR009080. tRNAsynth_1a_anticodon-bd. IPR013155. V/L/I-tRNA-synth_anticodon-bd. IPR009008. Val/Leu/Ile-tRNA-synth_Ia_edit. [Graphical view]
Gene3D	G3DSA:3.40.50.620. Rossmann-like_a/b/a_fold. 1 hit.
PANTHER	PTHR11946:SF9. Ile-tRNA-synt_Ia. 1 hit.
Pfam	PF08264. Anticodon_1. 1 hit. PF00133. tRNA-synt_1. 1 hit. [Graphical view]
PRINTS	PR00984. TRNASYNTHILE.
TIGRFAMs	TIGR00392. ileS. 1 hit.
PROSITE	PS00178. AA_TRNA_LIGASE_I. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

SYI2_PSEFL

Accession

Primary (citable) accession number: Q8L1B1
Secondary accession number(s): Q8GM72, Q8RL58

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 6, 2005
Last sequence update:	January 23, 2007
Last modified:	February 9, 2010
This is version 42 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)