Molecular and computational investigation of the skin microbiota associated with Pityriasis infection /
Mohamed Taha Abdelaziz,
Molecular and computational investigation of the skin microbiota associated with Pityriasis infection / دراسات جزيئية وحاسوبية للتجمعات الميكروبية الجلدية المرتبطة بعدوي النخالية المبرقشة by Mohamed Taha Abdelaziz ; Supervision Dr. Ramy Karam Aziz, Dr. Mariam Hassan Haikal, Dr. Dalia Ali Eldamacy. - 72 pages : illustrations ; 25 cm. + CD.
Thesis (M.Sc)-Cairo University, 2025.
Bibliography: pages 61-72.
Pityriasis versicolor is a superficial fungal infection that causes skin pigmentation lesions, mostly without any severe symptoms but with a high prevalence and incidence of recurrence. An altered skin microbial community with an increase in Malassezia species, predominately Malassezia furfur, together with the transformation of those pityrosporum Malassezia to their mycelial form, are reported as the main cause of the disease. Despite the substantial advances in studying the human skin microbiome over the past two decades, the distribution of M. furfur in different skin microbiomes, and the involvement of the skin bacteriome in pityriasis versicolor are not conclusive. This study was initiated to systematically determine the distribution of M. furfur in sequenced skin metagenomes and to experimentally investigate its association with skin bacteriome profiles, which may provide clues to the role of skin microbiota balance in the treatment of pityriasis versicolor. First, publicly available skin metagenomes were computationally analyzed to systematically determine the distribution of M. furfur and its relative abundance at different skin sites. Using BLASTN to map newly proposed marker genes to representative metagenomic datasets allowed the estimation of M. furfur relative abundance, which indicated a relative enrichment of M. furfur in retro auricular crease, antecubital fossa, and forehead samples. Among skin categories, sebaceous areas were the most significantly enriched in M. furfur, while in terms of exposure/occlusion, exposed areas had the highest relative abundance. Second, an experimental case-control study investigated how the skin bacteriome, its dysbiosis, and fungal colonization might be related to pityriasis versicolor infection. The study was conducted on 20 skin swabs (taken from the neck to the subclavius area) from ten patients with pityriasis versicolor and six swabs from healthy volunteers (healthy controls). For each patient, one swab was taken from the lesion, while the other from a non-lesion area. The bacteriome of the 26 samples was profiled by 16S rRNA amplicon sequencing. Bioinformatics analysis indicated that samples from healthy control were more diverse and significantly differed (p-value < 0.05) in their bacterial composition from patients with pityriasis versicolor samples (lesion and non-lesion samples). Betaproteobacteria and Alphaproteobacteria had lower relative abundance in pityriasis versicolor patient skin, while Gammaproteobacteria was slightly more abundant. On the genus level, Ochrobactrum was relative more abundant in healthy skin samples, while Facklamia was relatively more abundant in lesion and non-lesion samples of patients with pityriasis versicolor. In conclusion, skin fungal alteration associated with pityriasis versicolor correlated with remarkable skin bacterial dysbiosis, not only in skin lesions, but also in the non-lesion areas. This finding suggests that bacterial dysbiosis may correlate with pityriasis versicolor infection and recurrence. Moreover, identifying commonly altered disease-associated bacterial taxa is a first step towards potential intervention to restore normal diversity, thus reducing the risk pityriasis versicolor and improving patient recovery. تحتوي الرسالة على اربعة فصول. الفصل الاول يتضمن مقدمة حول الطرق المختلفة لتشييد مشتقات الثيينو]٢,٣-د[بيريميدين، ومقدمة موجزة عن موت الخلايا المبرمج، وإنزيمات مستقبلات التيروزين كيناز، وموت الخلايا المبرمج، بالإضافة إلى النشاط المضاد للسرطان لمشتقات الثينوبيريميدين. الفصل الثاني يعرض أهداف البحث وعرض المخططات التي توضح الطرق العملية التي صممت للحصول على هذه المركبات.
الفصل الثالث يتضمن المناقشة النظرية للجزء العملى، ومناقشة الأنشطة المضادة للسرطان والأنشطة الإنزيمية للمركبات الجديدة، ودراسة النمذجة الجزيئية، ومناقشة موجزة عن علاقة تركيب المركبات بفاعليتها. الفصل الرابع يشمل الخطوات العملية التي تم تنفيذها لتحضير المركبات الوسيطة والمستهدفة بالتفصيل، بالإضافة إلى خصائص المركبات التي تم تشييدها، وتحليل العناصر والبيانات الطيفية لهذه المركبات. هذا الفصل يغطي أيضا النشاط المضاد للسرطان في المختبر وفاعلية المركبات التي تم تشييدها حديثًا ضد إنزيم FLT-3 ، ونشاط موت الخلايا المبرمج للمركبات الأكثر فاعلية ودراسة النمذجة الجزيئية لها.
Text in English and abstract in Arabic & English.
Microbiology
الميكروبيولوجيا الطبية
16S rRNA gene sequencing BLASTN Dysbiosis Malassezia furfur Metagenomics Pityriasis versicolor
616.01
Molecular and computational investigation of the skin microbiota associated with Pityriasis infection / دراسات جزيئية وحاسوبية للتجمعات الميكروبية الجلدية المرتبطة بعدوي النخالية المبرقشة by Mohamed Taha Abdelaziz ; Supervision Dr. Ramy Karam Aziz, Dr. Mariam Hassan Haikal, Dr. Dalia Ali Eldamacy. - 72 pages : illustrations ; 25 cm. + CD.
Thesis (M.Sc)-Cairo University, 2025.
Bibliography: pages 61-72.
Pityriasis versicolor is a superficial fungal infection that causes skin pigmentation lesions, mostly without any severe symptoms but with a high prevalence and incidence of recurrence. An altered skin microbial community with an increase in Malassezia species, predominately Malassezia furfur, together with the transformation of those pityrosporum Malassezia to their mycelial form, are reported as the main cause of the disease. Despite the substantial advances in studying the human skin microbiome over the past two decades, the distribution of M. furfur in different skin microbiomes, and the involvement of the skin bacteriome in pityriasis versicolor are not conclusive. This study was initiated to systematically determine the distribution of M. furfur in sequenced skin metagenomes and to experimentally investigate its association with skin bacteriome profiles, which may provide clues to the role of skin microbiota balance in the treatment of pityriasis versicolor. First, publicly available skin metagenomes were computationally analyzed to systematically determine the distribution of M. furfur and its relative abundance at different skin sites. Using BLASTN to map newly proposed marker genes to representative metagenomic datasets allowed the estimation of M. furfur relative abundance, which indicated a relative enrichment of M. furfur in retro auricular crease, antecubital fossa, and forehead samples. Among skin categories, sebaceous areas were the most significantly enriched in M. furfur, while in terms of exposure/occlusion, exposed areas had the highest relative abundance. Second, an experimental case-control study investigated how the skin bacteriome, its dysbiosis, and fungal colonization might be related to pityriasis versicolor infection. The study was conducted on 20 skin swabs (taken from the neck to the subclavius area) from ten patients with pityriasis versicolor and six swabs from healthy volunteers (healthy controls). For each patient, one swab was taken from the lesion, while the other from a non-lesion area. The bacteriome of the 26 samples was profiled by 16S rRNA amplicon sequencing. Bioinformatics analysis indicated that samples from healthy control were more diverse and significantly differed (p-value < 0.05) in their bacterial composition from patients with pityriasis versicolor samples (lesion and non-lesion samples). Betaproteobacteria and Alphaproteobacteria had lower relative abundance in pityriasis versicolor patient skin, while Gammaproteobacteria was slightly more abundant. On the genus level, Ochrobactrum was relative more abundant in healthy skin samples, while Facklamia was relatively more abundant in lesion and non-lesion samples of patients with pityriasis versicolor. In conclusion, skin fungal alteration associated with pityriasis versicolor correlated with remarkable skin bacterial dysbiosis, not only in skin lesions, but also in the non-lesion areas. This finding suggests that bacterial dysbiosis may correlate with pityriasis versicolor infection and recurrence. Moreover, identifying commonly altered disease-associated bacterial taxa is a first step towards potential intervention to restore normal diversity, thus reducing the risk pityriasis versicolor and improving patient recovery. تحتوي الرسالة على اربعة فصول. الفصل الاول يتضمن مقدمة حول الطرق المختلفة لتشييد مشتقات الثيينو]٢,٣-د[بيريميدين، ومقدمة موجزة عن موت الخلايا المبرمج، وإنزيمات مستقبلات التيروزين كيناز، وموت الخلايا المبرمج، بالإضافة إلى النشاط المضاد للسرطان لمشتقات الثينوبيريميدين. الفصل الثاني يعرض أهداف البحث وعرض المخططات التي توضح الطرق العملية التي صممت للحصول على هذه المركبات.
الفصل الثالث يتضمن المناقشة النظرية للجزء العملى، ومناقشة الأنشطة المضادة للسرطان والأنشطة الإنزيمية للمركبات الجديدة، ودراسة النمذجة الجزيئية، ومناقشة موجزة عن علاقة تركيب المركبات بفاعليتها. الفصل الرابع يشمل الخطوات العملية التي تم تنفيذها لتحضير المركبات الوسيطة والمستهدفة بالتفصيل، بالإضافة إلى خصائص المركبات التي تم تشييدها، وتحليل العناصر والبيانات الطيفية لهذه المركبات. هذا الفصل يغطي أيضا النشاط المضاد للسرطان في المختبر وفاعلية المركبات التي تم تشييدها حديثًا ضد إنزيم FLT-3 ، ونشاط موت الخلايا المبرمج للمركبات الأكثر فاعلية ودراسة النمذجة الجزيئية لها.
Text in English and abstract in Arabic & English.
Microbiology
الميكروبيولوجيا الطبية
16S rRNA gene sequencing BLASTN Dysbiosis Malassezia furfur Metagenomics Pityriasis versicolor
616.01