Contribution of the DDDD motif of H. influenzae e (P4) to phosphomonoesterase activity and heme transport

FEBS Letters

Zlotnick, Gary W²  Smith, Arnold L¹  Green, Bruce A²  Reilly, Thomas J¹ 

[1] Department of Molecular Microbiology and Immunology, University of Missouri Medical School, DC044.00, M616 Medical Sciences Bldg., Columbia, MO 65212, USA;Wyeth-Lederle Vaccines, 211 Bailey Road West, Henrietta, NY 14586-9728, USA

关键词: Lipoprotein e (P4);    DDDD phosphomonoesterase;    Heme transport;    Haemophilus influenzae;    ALA;    aminolevulinic acid;    e (P4);    H. influenzae lipoprotein e (P4);    LB;    Luria Bertani;    NSAP;    non-specific acid phosphatase;    pNPP;    p-nitrophenylphosphate;   

DOI  :  10.1016/S0014-5793(01)02294-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Haemophilus influenzae lipoprotein e (P4) is a member of the DDDD phosphohydrolase superfamily and mediates heme transport. Each of the aspartate residues of the signature motif is required for phosphomonoesterase activity, as none of the e (P4) single D mutants (D64A, D66A, D181N, and D185A) possessed detectable phosphomonoesterase activity. These results suggest that the signature motif is essential to the phosphomonoesterase activity of lipoprotein e (P4). When assessed for phosphomonoesterase-dependent heme transport activity in Escherichia coli hemA strains, plasmids containing D181N and D185A retained heme transport as indicated by aerobic growth while D64A and D66A did not. We conclude that phosphomonoesterase activity is not required for heme transport.

【 授权许可】

Unknown