TY  - JOUR
A1  - Zahn, Sebastian
A1  - Kubatova, Nina
A1  - Pyper, Dennis Joshua
A1  - Cassidy, Liam
A1  - Saxena, Krishna
A1  - Tholey, Andreas
A1  - Schwalbe, Harald
A1  - Soppa, Jörg
T1  - Biological functions, genetic and biochemical characterization, and NMR structure determination of the small zinc finger protein HVO_2753 from Haloferax volcanii
T2  - The FEBS journal
N2  - The genome of the halophilic archaeon Haloferax volcanii encodes more than 40 one-domain zinc finger µ-proteins. Only one of these, HVO_2753, contains four C(P)XCG motifs, suggesting the presence of two zinc binding pockets (ZBPs). Homologs of HVO_2753 are widespread in many euryarchaeota. An in frame deletion mutant of HVO_2753 grew indistinguishably from the wild-type in several media, but had a severe defect in swarming and in biofilm formation. For further analyses, the protein was produced homologously as well as heterologously in Escherichia coli. HVO_2753 was stable and folded in low salt, in contrast to many other haloarchaeal proteins. Only haloarchaeal HVO_2753 homologs carry a very hydrophilic N terminus, and NMR analysis showed that this region is very flexible and not part of the core structure. Surprisingly, both NMR analysis and a fluorimetric assay revealed that HVO_2753 binds only one zinc ion, despite the presence of two ZBPs. Notably, the analysis of cysteine to alanine mutant proteins by NMR as well by in vivo complementation revealed that all four C(P)XCG motifs are essential for folding and function. The NMR solution structure of the major conformation of HVO_2753 was solved. Unexpectedly, it was revealed that ZBP1 was comprised of C(P)XCG motifs 1 and 3, and ZBP2 was comprised of C(P)XCG motifs 2 and 4. There are several indications that ZBP2 is occupied by zinc, in contrast to ZBP1. To our knowledge, this study represents the first in-depth analysis of a zinc finger µ-protein in all three domains of life.
KW  - µ-protein
KW  - Haloferax volcanii
KW  - NMR solution structure
KW  - small protein
KW  - zinc finger
Y1  - 2020
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63853
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-638531
SN  - 1439-7633
N1  - The collaborative project was funded by the German Research Council (Deutsche Forschungsgemeinschaft, DFG) in the framework of the Priority Program SPP2002 'Small proteins in prokaryotes' (www.spp2002.uni-kiel.de). The projects of the groups of JS and HS and the Z1 project headed by AT were involved, and the project numbers are JS264/26-1, SCHW 701/21-1, and TH872/10-1. Open access funding enabled and organized by ProjektDEAL.
VL  - 288
IS  - 6
SP  - 2042
EP  - 2062
PB  - Wiley-Blackwell
CY  - Oxford [u.a.]
ER  -