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@PHDTHESIS{Mertinkus:638475,
author = {Mertinkus, Klara Rebecca},
othercontributors = {Schwalbe, Harald and Grininger, Martin},
title = {{B}iophysical investigation of {RNA} folding:
{NMR}-spectroscopic investigation of stem-loop 5 from
{SARS}-{C}o{V}-2},
school = {Johann Wolfgang-Goethe-Universität Frankfurt},
type = {Dissertation},
reportid = {PUBDB-2025-04082},
pages = {260},
year = {2025},
note = {Dissertation, Johann Wolfgang-Goethe-Universität
Frankfurt, 2025},
abstract = {When in 2020 the virus for the severe acute respiratory
syndrome coronavirus type 2 (SARS-CoV-2) hitthe world, the
response of the scientific community was tremendous.
Scientists used not only state-of-the-art methodology but
also reacted by developing effective countermeasures. Our
group joined thisgoal with their expertise in nuclear
magnetic resonance (NMR) spectroscopy. With our
specialization inNMR of biomolecules like proteins and
ribonucleic acids (RNAs) we coordinated a global network
calledCOVID19-nmr (https://covid19-nmr.de). Substantial
efforts in the Frankfurt team provided the basis forthe
understanding of viral proteins and genomic RNAs. Other
research groups identified viralcomponents of the SARS-CoV-2
coronavirus which allowed us to prioritize potential targets
from anNMR and structural point of view. With our results,
investigations were expanded: We screened viraltargets to
libraries of low molecular weight ligands as start for
medicinal chemistry campaigns.To study possible viral
targets and the effects of pharmacological reagents the
affected biologicalsystems and mechanisms need to be
understood. The knowledge of a biological component,
itsstructure and behavior, are key to the effective
influence of cellular processes resulting from the
viralinfection. In most cases, a reductionist approach is
used to study the identified participants, as the
overallview of the system can give the researcher an
overwhelming amount of information that needs to
bedeciphered. By changing the perspective and looking at the
nature and behavior of individual systems,the information
gain can be increased. The current research objective does
not only benefit from theresults produced at present, but
also from results achieved previously. Especially in case of
the SARS-CoV-2 virus, the comparison to earlier known and
human infecting coronaviruses provided a large poolof
knowledge for scientific studies. However, the comparisons
also showed that despite the previousknowledge, the data
were not fully sufficient, leaving us with the possibility
for vaccination but no curefor the coronavirus disease 2019
(COVID-19) caused by the virus. Therefore, research attempts
tounderstand the virus and its constituents are of ongoing
interest.In this work, I will present research results for
structural investigation of the target RNA $5_SL5,$ which
isthe 5th element of the 59-terminal untranslated region
(UTR) of the SARS-CoV-2 viral genome. Due tothe location of
the AUG start codon within the sequence it is the start side
for the translation of the openreading frame (ORF) 1a/b,
which encodes for 16 non-structural proteins (nsp) of the
virus. Theinvestigation of the SL5 target was split due to
its large sequence and structural fold. I will show
thepossibility to investigate large RNA systems like this by
the reductionism approach of divide-and-conquer. Several
methods of structural and folding studies of RNA were used
for an initial evaluation ofthe applicability of the
divide-and-conquer approach, providing a comprehensive
global view of thesystem. With this, the focus of this work
were the designed sub-elements of the SL5 element and
thepossibility to transfer insight gained from the
individual sub-elements to the larger system. The methodNMR
was extensively used to obtain a detailed chemical shift
characterization of the sub-elements.Furthermore,
NMR-experimental methods were used for the determination of
individual base-pairstabilities as well as for the
delineation of local dynamics. The impact of evolutionary
changes(mutations) on the elements, hence by sequence
alteration like those found in variants of concern
(VoC),were investigated. In summary, the work is able to
show the comparability of gathered information onthe small
elements to the full-length system. It will also report on
the difficulties arising when investigatinglarger RNA
systems with NMR. Finally, a comparison of the combined
structure-biological informationof the system will be
presented.The investigations undertaken in this thesis are
not able to clarify biological relevance or function on
theSL5 within the virus machinery, but it gives detailed
insight in an interesting target structure, which
isconserved throughout the Coronaviridae. Therefore, this
research provide an addition to the pool ofknowledge, which
may drive future investigations.},
cin = {EMBL-User},
cid = {I:(DE-H253)EMBL-User-20120814},
pnm = {6G3 - PETRA III (DESY) (POF4-6G3)},
pid = {G:(DE-HGF)POF4-6G3},
experiment = {EXP:(DE-H253)P-P12-20150101},
typ = {PUB:(DE-HGF)11},
urn = {urn:nbn:de:hebis:30:3-920099},
doi = {10.3204/PUBDB-2025-04082},
url = {https://bib-pubdb1.desy.de/record/638475},
}