PMID- 25137435
OWN - NLM
STAT- MEDLINE
DCOM- 20141121
LR  - 20211021
IS  - 1520-4995 (Electronic)
IS  - 0006-2960 (Print)
IS  - 0006-2960 (Linking)
VI  - 53
IP  - 35
DP  - 2014 Sep 9
TI  - Evidence that the C-terminal domain of a type B PutA protein contributes to 
      aldehyde dehydrogenase activity and substrate channeling.
PG  - 5661-73
LID - 10.1021/bi500693a [doi]
AB  - Proline utilization A (PutA) is a bifunctional enzyme that catalyzes the 
      oxidation of proline to glutamate. Structures of type A PutAs have revealed the 
      catalytic core consisting of proline dehydrogenase (PRODH) and 
      Delta(1)-pyrroline-5-carboxylate dehydrogenase (P5CDH) modules connected by a 
      substrate-channeling tunnel. Type B PutAs also have a C-terminal domain of 
      unknown function (CTDUF) that is absent in type A PutAs. Small-angle X-ray 
      scattering (SAXS), mutagenesis, and kinetics are used to determine the 
      contributions of this domain to PutA structure and function. The 1127-residue 
      Rhodobacter capsulatus PutA (RcPutA) is used as a representative CTDUF-containing 
      type B PutA. The reaction progress curve for the coupled PRODH-P5CDH activity of 
      RcPutA does not exhibit a time lag, implying a substrate channeling mechanism. 
      RcPutA is monomeric in solution, which is unprecedented for PutAs. SAXS rigid 
      body modeling with target-decoy validation is used to build a model of RcPutA. On 
      the basis of homology to aldehyde dehydrogenases (ALDHs), the CTDUF is predicted 
      to consist of a beta-hairpin fused to a noncatalytic Rossmann fold domain. The 
      predicted tertiary structural interactions of the CTDUF resemble the quaternary 
      structural interactions in the type A PutA dimer interface. The model is tested 
      by mutagenesis of the dimerization hairpin of a type A PutA and the CTDUF hairpin 
      of RcPutA. Similar functional phenotypes are observed in the two sets of 
      variants, supporting the hypothesis that the CTDUF mimics the type A PutA dimer 
      interface. These results suggest annotation of the CTDUF as an ALDH superfamily 
      domain that facilitates P5CDH activity and substrate channeling by stabilizing 
      the aldehyde-binding site and sealing the substrate-channeling tunnel from the 
      bulk medium.
FAU - Luo, Min
AU  - Luo M
AD  - Department of Chemistry, University of Missouri-Columbia , Columbia, Missouri 
      65211, United States.
FAU - Christgen, Shelbi
AU  - Christgen S
FAU - Sanyal, Nikhilesh
AU  - Sanyal N
FAU - Arentson, Benjamin W
AU  - Arentson BW
FAU - Becker, Donald F
AU  - Becker DF
FAU - Tanner, John J
AU  - Tanner JJ
LA  - eng
GR  - GM065546/GM/NIGMS NIH HHS/United States
GR  - P30GM103335/GM/NIGMS NIH HHS/United States
GR  - R01 GM065546/GM/NIGMS NIH HHS/United States
GR  - R01 GM061068/GM/NIGMS NIH HHS/United States
GR  - GM061068/GM/NIGMS NIH HHS/United States
GR  - P30 GM103335/GM/NIGMS NIH HHS/United States
GR  - R01 GM105404/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20140826
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Bacterial Proteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (PutA protein, Bacteria)
RN  - 0 (Recombinant Proteins)
RN  - EC 1.2.1.3 (Aldehyde Dehydrogenase)
SB  - IM
MH  - Aldehyde Dehydrogenase/*chemistry/genetics/*metabolism
MH  - Amino Acid Sequence
MH  - Amino Acid Substitution
MH  - Bacterial Proteins/*chemistry/genetics/*metabolism
MH  - Bradyrhizobium/genetics/metabolism
MH  - Catalytic Domain
MH  - Genes, Bacterial
MH  - Kinetics
MH  - Membrane Proteins/*chemistry/genetics/*metabolism
MH  - Models, Molecular
MH  - Molecular Sequence Data
MH  - Mutagenesis, Site-Directed
MH  - Protein Conformation
MH  - Protein Interaction Domains and Motifs
MH  - Recombinant Proteins/chemistry/genetics/metabolism
MH  - Rhodobacter capsulatus/genetics/*metabolism
MH  - Scattering, Small Angle
MH  - Sequence Homology, Amino Acid
MH  - Structural Homology, Protein
MH  - Substrate Specificity
MH  - X-Ray Diffraction
PMC - PMC4159212
EDAT- 2014/08/20 06:00
MHDA- 2014/12/15 06:00
PMCR- 2015/08/19
CRDT- 2014/08/20 06:00
PHST- 2014/08/20 06:00 [entrez]
PHST- 2014/08/20 06:00 [pubmed]
PHST- 2014/12/15 06:00 [medline]
PHST- 2015/08/19 00:00 [pmc-release]
AID - 10.1021/bi500693a [doi]
PST - ppublish
SO  - Biochemistry. 2014 Sep 9;53(35):5661-73. doi: 10.1021/bi500693a. Epub 2014 Aug 
      26.