MVL_MICVR
ID MVL_MICVR Reviewed; 114 AA.
AC Q9RHG4;
DT 09-FEB-2010, integrated into UniProtKB/Swiss-Prot.
DT 01-MAY-2000, sequence version 1.
DT 03-AUG-2022, entry version 51.
DE RecName: Full=Lectin MVL;
DE AltName: Full=Mannan-binding lectin;
DE AltName: Full=N-acetyl-beta-glucosaminidase;
DE EC=3.2.1.-;
DE AltName: Full=Oligomannoside-binding lectin;
GN Name=mvl;
OS Microcystis viridis.
OC Bacteria; Cyanobacteria; Oscillatoriophycideae; Chroococcales;
OC Microcystaceae; Microcystis.
OX NCBI_TaxID=44822;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 2-22, FUNCTION,
RP HEMAGGLUTININATING ACTIVITY, MANNAN-BINDING, BIOPHYSICOCHEMICAL PROPERTIES,
RP SUBCELLULAR LOCATION, AND INDUCTION.
RC STRAIN=NIES-102;
RX PubMed=10600484; DOI=10.1006/bbrc.1999.1749;
RA Yamaguchi M., Ogawa T., Muramoto K., Kamio Y., Jimbo M., Kamiya H.;
RT "Isolation and characterization of a mannan-binding lectin from the
RT freshwater cyanobacterium (blue-green algae) Microcystis viridis.";
RL Biochem. Biophys. Res. Commun. 265:703-708(1999).
RN [2]
RP FUNCTION AS HIV-1 INHIBITORY PROTEIN, SUBUNIT, AND CARBOHYDRATE
RP SPECIFICITY.
RC STRAIN=NIES-102;
RX PubMed=15165858; DOI=10.1016/j.jmb.2004.04.019;
RA Bewley C.A., Cai M., Ray S., Ghirlando R., Yamaguchi M., Muramoto K.;
RT "New carbohydrate specificity and HIV-1 fusion blocking activity of the
RT cyanobacterial protein MVL: NMR, ITC and sedimentation equilibrium
RT studies.";
RL J. Mol. Biol. 339:901-914(2004).
RN [3]
RP X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF APOPROTEIN AND IN COMPLEX WITH
RP MAN3GLCNAC2, SUBUNIT, AND DOMAIN.
RX PubMed=15937331; DOI=10.1074/jbc.m504642200;
RA Williams D.C. Jr., Lee J.Y., Cai M., Bewley C.A., Clore G.M.;
RT "Crystal structures of the HIV-1 inhibitory cyanobacterial protein MVL free
RT and bound to Man3GlcNAc2: structural basis for specificity and high-
RT affinity binding to the core pentasaccharide from n-linked
RT oligomannoside.";
RL J. Biol. Chem. 280:29269-29276(2005).
RN [4]
RP STRUCTURE BY NMR OF MUTANT ALA-76 IN COMPLEX WITH GLCNAC3, GLYCOSIDASE
RP ACTIVITY, CATALYTIC ACTIVITY, AND MUTAGENESIS OF ASP-76.
RX PubMed=19856962; DOI=10.1021/ja905929c;
RA Shahzad-ul-Hussan S., Cai M., Bewley C.A.;
RT "Unprecedented glycosidase activity at a lectin carbohydrate-binding site
RT exemplified by the cyanobacterial lectin MVL.";
RL J. Am. Chem. Soc. 131:16500-16508(2009).
CC -!- FUNCTION: Carbohydrate-binding protein that binds oligomannosides such
CC as Man(6)GlcNAc(2) with sub-micromolar affinities. The specificity of
CC MVL is unique in that its minimal target comprises the Man-alpha-
CC (1->6)-Man-beta-(1->4)-GlcNAc-beta-(1->4)-GlcNAc tetrasaccharide core
CC (Man(2)A) found in N-linked oligomannosides. Displays
CC hemagglutininating activity on rabbit, horse and hen erythrocytes. This
CC activity is inhibited by yeast mannan. Does not bind mono- and
CC disaccharides. Inhibits HIV-1 envelope-mediated cell fusion at
CC nanomolar concentrations through carbohydrate-mediated interactions
CC with high-mannose residues on the surface of the HIV envelope
CC glycoprotein gp120.
CC -!- FUNCTION: Unexpectedly for a lectin, one of the 2 oligomannose binding
CC sites of MVL can catalyze the cleavage of chitin fragments (such as
CC chitotriose, i.e. GlcNAc(3) or GlcNAc-beta-(1->4)-GlcNAcbeta-(1->4)-
CC GlcNAc, and chitotetraose, i.e. GlcNAc(4)) to GlcNAc. This weak beta-
CC 1,4-glycosidase activity is restricted to the C-terminal carbohydrate-
CC binding site. Does not cleave Man(3)GlcNAc(2) or the tetrasaccharide
CC Man(2)A. {ECO:0000269|PubMed:19856962}.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC pH dependence:
CC Displays hemagglutinating activity from pH 5 to 8, but is inactive
CC beyond these pHs. {ECO:0000269|PubMed:10600484};
CC Temperature dependence:
CC Half the hemagglutinating activity is maintained by heating at 50
CC degrees Celsius for 3 hours. Is inactive by heating at 60 degrees
CC Celsius for 10 minutes. {ECO:0000269|PubMed:10600484};
CC -!- SUBUNIT: Homodimer. {ECO:0000269|PubMed:15165858,
CC ECO:0000269|PubMed:15937331, ECO:0000269|PubMed:19856962}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000305|PubMed:10600484}.
CC -!- INDUCTION: Induced under low nutrient or anoxic conditions.
CC {ECO:0000269|PubMed:10600484}.
CC -!- DOMAIN: Each monomer contains 2 structurally homologous domains with
CC high sequence similarity connected by a short five-amino acid residue
CC linker. Intriguingly, a water-filled channel is observed between the 2
CC monomers. {ECO:0000269|PubMed:15937331}.
CC -!- MISCELLANEOUS: Binds 2 carbohydrate molecules per monomer. The 2
CC symmetrically related-binding sites exhibit similar affinities relative
CC to one other.
CC -!- MISCELLANEOUS: The structural studies suggest catalysis likely occurs
CC through proton relay via a 'proton wire'.
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DR EMBL; AB036699; BAA89413.1; -; Genomic_DNA.
DR PDB; 1ZHQ; X-ray; 1.90 A; A/B/C/D/E/F/G/H=2-114.
DR PDB; 1ZHS; X-ray; 1.80 A; A/B/C/D/E/F/G/H=2-114.
DR PDBsum; 1ZHQ; -.
DR PDBsum; 1ZHS; -.
DR AlphaFoldDB; Q9RHG4; -.
DR SMR; Q9RHG4; -.
DR UniLectin; Q9RHG4; -.
DR EvolutionaryTrace; Q9RHG4; -.
DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR GO; GO:0030246; F:carbohydrate binding; IEA:UniProtKB-KW.
DR GO; GO:0016798; F:hydrolase activity, acting on glycosyl bonds; IEA:UniProtKB-KW.
DR GO; GO:0008152; P:metabolic process; IEA:UniProtKB-KW.
DR GO; GO:0050688; P:regulation of defense response to virus; IEA:UniProtKB-KW.
DR InterPro; IPR021992; MVL.
DR Pfam; PF12151; MVL; 2.
PE 1: Evidence at protein level;
KW 3D-structure; Antiviral protein; Cytoplasm; Direct protein sequencing;
KW Glycosidase; Hemagglutinin; Hydrolase; Lectin; Repeat.
FT INIT_MET 1
FT /note="Removed"
FT /evidence="ECO:0000269|PubMed:10600484"
FT CHAIN 2..114
FT /note="Lectin MVL"
FT /id="PRO_0000391620"
FT REPEAT 2..55
FT /note="1"
FT REPEAT 61..114
FT /note="2"
FT REGION 56..60
FT /note="Linker"
FT BINDING 12..16
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="1"
FT BINDING 20
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="1"
FT BINDING 36..44
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="1"
FT BINDING 71..75
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="2"
FT BINDING 79
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="2"
FT BINDING 95..103
FT /ligand="a carbohydrate"
FT /ligand_id="ChEBI:CHEBI:16646"
FT /ligand_label="2"
FT MUTAGEN 76
FT /note="D->A: Loss of N-acetyl-beta-glucosaminidase
FT activity. No effect on anti-HIV activity."
FT /evidence="ECO:0000269|PubMed:19856962"
FT STRAND 3..11
FT /evidence="ECO:0007829|PDB:1ZHS"
FT HELIX 16..29
FT /evidence="ECO:0007829|PDB:1ZHS"
FT STRAND 33..42
FT /evidence="ECO:0007829|PDB:1ZHS"
FT TURN 43..45
FT /evidence="ECO:0007829|PDB:1ZHS"
FT STRAND 46..56
FT /evidence="ECO:0007829|PDB:1ZHS"
FT STRAND 60..70
FT /evidence="ECO:0007829|PDB:1ZHS"
FT HELIX 75..87
FT /evidence="ECO:0007829|PDB:1ZHS"
FT TURN 88..90
FT /evidence="ECO:0007829|PDB:1ZHS"
FT STRAND 91..101
FT /evidence="ECO:0007829|PDB:1ZHS"
FT TURN 102..104
FT /evidence="ECO:0007829|PDB:1ZHS"
FT STRAND 105..114
FT /evidence="ECO:0007829|PDB:1ZHS"
SQ SEQUENCE 114 AA; 12368 MW; 6D1735A1C971D186 CRC64;
MASYKVNIPA GPLWSNAEAQ QVGPKIAAAH QGNFTGQWTT VVESAMSVVE VELQVENTGI
HEFKTDVLAG PLWSNDEAQK LGPQIAASYG AEFTGQWRTI VEGVMSVIQI KYTF
