Dr Hasan Yesilkaya

Associate professor

School/Department: Respiratory Sciences, Department of

Telephone: +44 (0)116 223 1401



I studied veterinary medicine at Ankara University Turkey. After completion of my PhD in Leicester on oxidative stress resistance of important human pathogen Streptococcus pneumoniae under the supervision of Prof Peter Andrew I worked in Utrecht as an EMBO fellow then moved to Aberdeen University where I studied transposable elements of Mycobacterium tuberculosis as a postdoctoral fellow. Since 2003 I have been working as a research fellow (2003-2012) lecturer (2012-2020) then as an associate professor (2020 onward) at the University of Leicester.


Microbes encounter fluctuating nutrient and physical environments in host tissues. In this dynamic milieu bacteria should be able to obtain the host nutrients and metabolise them for efficient replication and virulence. However our knowledge of how microbes maintain their survival in vivo is very limited. I have been studying microbial physiology and metabolic adaptation using Streptococcus pneumoniae as a model organism to understand microbial in host survival and virulence. My ultimate research goals are to define critical metabolic microbial networks associated with virulence in different host niches and target these pathways pharmaceutically. The particular topics I study include: mechanisms by which microbes cleave and metabolise host-derived nutrients the impact of genetic and environmental factors on microbial colonisation and virulence the role of quorum sensing systems on pneumococcal physiology and in host survival.


1: Gazioglu O, Kareem BO, Afzal M, Shafeeq S, Kuipers OP, Ulijasz AT, Andrew PW,
Yesilkaya H. Glutamate dehydrogenase (GdhA) of <i>Streptococcus pneumoniae</i>
is required for high temperature adaptation. Infect Immun. 2021 Sep
7:IAI0040021. doi: 10.1128/IAI.00400-21. Epub ahead of print. PMID: 34491792.

2: Shlla B, Gazioglu O, Shafeeq S, Manzoor I, Kuipers OP, Ulijasz A, Hiller NL,
Andrew PW, Yesilkaya H. The Rgg1518 transcriptional regulator is a necessary
facet of sugar metabolism and virulence in Streptococcus pneumoniae. Mol
Microbiol. 2021 Jul 30. doi: 10.1111/mmi.14788. Epub ahead of print. PMID:

3: Aggarwal SD, Yesilkaya H, Dawid S, Hiller NL. The pneumococcal social
network. PLoS Pathog. 2020 Oct 29;16(10):e1008931. doi:
10.1371/journal.ppat.1008931. PMID: 33119698; PMCID: PMC7595303.

4: Najmuldeen H, Alghamdi R, Alghofaili F, Yesilkaya H. Functional assessment of
microbial superoxide dismutase isozymes suggests a differential role for each
isozyme. Free Radic Biol Med. 2019 Apr;134:215-228. doi:
10.1016/j.freeradbiomed.2019.01.018. Epub 2019 Jan 15. PMID: 30658083.

5: Aggarwal SD, Eutsey R, West-Roberts J, Domenech A, Xu W, Abdullah IT,
Mitchell AP, Veening JW, Yesilkaya H, Hiller NL. Function of BriC peptide in the
pneumococcal competence and virulence portfolio. PLoS Pathog. 2018 Oct
11;14(10):e1007328. doi: 10.1371/journal.ppat.1007328. PMID: 30308062; PMCID:

6: Glanville DG, Han L, Maule AF, Woodacre A, Thanki D, Abdullah IT, Morrissey
JA, Clarke TB, Yesilkaya H, Silvaggi NR, Ulijasz AT. RitR is an archetype for a
novel family of redox sensors in the streptococci that has evolved from two-
component response regulators and is required for pneumococcal colonization.
PLoS Pathog. 2018 May 11;14(5):e1007052. doi: 10.1371/journal.ppat.1007052.
PMID: 29750817; PMCID: PMC5965902.

7: Motib A, Guerreiro A, Al-Bayati F, Piletska E, Manzoor I, Shafeeq S, Kadam A,
Kuipers O, Hiller L, Cowen T, Piletsky S, Andrew PW, Yesilkaya H. Modulation of
Quorum Sensing in a Gram-Positive Pathogen by Linear Molecularly Imprinted
Polymers with Anti-infective Properties. Angew Chem Int Ed Engl. 2017 Dec
22;56(52):16555-16558. doi: 10.1002/anie.201709313. Epub 2017 Dec 1. PMID:

8: Kadam A, Eutsey RA, Rosch J, Miao X, Longwell M, Xu W, Woolford CA, Hillman
T, Motib AS, Yesilkaya H, Mitchell AP, Hiller NL. Promiscuous signaling by a
regulatory system unique to the pandemic PMEN1 pneumococcal lineage. PLoS
Pathog. 2017 May 18;13(5):e1006339. doi: 10.1371/journal.ppat.1006339. PMID:
28542565; PMCID: PMC5436883.

9: Kahya HF, Andrew PW, Yesilkaya H. Deacetylation of sialic acid by esterases
potentiates pneumococcal neuraminidase activity for mucin utilization,
colonization and virulence. PLoS Pathog. 2017 Mar 3;13(3):e1006263. doi:
10.1371/journal.ppat.1006263. PMID: 28257499; PMCID: PMC5352144.

10: Robb M, Hobbs JK, Woodiga SA, Shapiro-Ward S, Suits MD, McGregor N, Brumer
H, Yesilkaya H, King SJ, Boraston AB. Molecular Characterization of N-glycan
Degradation and Transport in Streptococcus pneumoniae and Its Contribution to
Virulence. PLoS Pathog. 2017 Jan 5;13(1):e1006090. doi:
10.1371/journal.ppat.1006090. PMID: 28056108; PMCID: PMC5215778.


Topics available for supervision The impact of in vivo derived sugars on bacterial physiology and virulence. Oxidative stress response of pathogenic bacteria.


I am a Fellow of the Higher Education Academy. I teach microbiology modules in undergraduate and postgraduate courses.

Press and media

Microbial virulence infectivity future antiinfectives.
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