Molecular Profiling of Microbial Communities Associated with a Potential Mud Volcano (Düzce, NW-Türkiye)

Öz

The geographic distribution of mud volcanoes is contingent upon geological processes, with the majority occurring in regions of recent tectonic activity, particularly within compressional zones. The current understanding of microorganisms involved in the anaerobic oxidation of methane in these settings is largely derived from studies of methane seep environments, where high concentrations of methane and sulfate sustain the high activity of syntrophic archaeal and bacterial consortia. This study was designed to investigate the microbial communities within a potential mud volcano observed following the Ml=6.0 earthquake that occurred in Düzce Province, Türkiye, in 2022. In this context, mud and water samples were collected in November 2023 to characterize the initial stage of a potential mud volcano. To determine microbial diversity and abundance, gene regions specific to the BACT, ARC, ANME-1, MCRA, SRB2, DSS, and DBB groups were quantified using Real-Time Quantitative PCR (qPCR). The highest bacterial abundance (1.52 × 10¹⁰ gene copies g⁻¹) was observed in the mud sample. Conversely, the lowest abundance was recorded for the Desulfobulbus group (2.49 × 10² gene copies mL⁻¹) in the water sample. This research represents the first investigation in Türkiye to assess the presence and abundance of archaeal and bacterial groups in a potential mud volcano located in an onshore setting. The mechanisms of formation, structural characteristics, and microbial diversity of terrestrial mud volcanoes may be further elucidated using advanced techniques such as phylogenetic analysis, radioisotope measurements, lipid biomarker analysis, and isotopic investigations.

Anahtar Kelimeler

• Archaea
• Bacteria
• Mud volcano
• Düzce
• Microbial abundance

Proje Numarası

FHD-2023-3225

Olası Bir Çamur Volkanı (Düzce, KB-Türkiye) İlişkili Mikrobiyal Toplulukların Moleküler Profili

Öz

Çamur volkanlarının coğrafi oluşumu jeolojik olaylara bağlıdır ve bunların çoğunluğu yakın zamandaki tektonik aktivite alanlarında, özellikle de sıkışma bölgelerinde meydana gelmektedir. Bu alanlarda anaerobik metan oksidasyonunda rol oynayan mikroorganizmalar hakkındaki mevcut bilgi birikimi, yüksek metan ve sülfat konsantrasyonlarının arke ve bakteri sintrofik ilişkilerinin yüksek aktivitesini desteklediği metan sızdıran ortamların çalışmalarına dayanmaktadır. 2022 yılında Düzce ilinde (Türkiye) gerçekleşen Ml=6.0 büyüklüğündeki depremden sonra gözlenen olası bir çamur volkanında mikrobiyolojik toplulukların araştırılması amacıyla çalışma planlanmıştır. Bu kapsamda, Düzce ilinde olası bir çamur volkanının başlangıç aşamasının araştırılmasına yönelik olarak, 2023 yılı Kasım ayında çamur ve su örnekleri toplanmıştır. Çalışmada mikrobiyal çeşitliliğin ve bolluğun belirlenmesinde; BACT, ARC, ANME-1, MCRA, SRB2, DSS ve DBB gruplarına ait gen bölgeleri Real time quantitative PCR (qPCR) ile belirlenmiştir. En yüksek bakteri bolluğu (1.52x1010 gen kopya sayısı/gr) çamur örneğinde gözlenmiştir. En düşük yoğunluğa sahip grup su örneğinde Desulfobulbus (2.49x102 gen kopya sayısı/mL) olarak saptanmıştır. Düzce ili çamur volkanında yürütülen bu çalışma, arke ve bakteri gruplarının varlığı ve bolluğunun araştırıldığı, ülkemizde karasal bir ortamda varlığı bilinen bir çamur volkanında gerçekleştirilen ilk çalışma olma özelliğini taşımaktadır. Filogenetik analizler, radyoizotop ölçümleri, lipit analizleri ve izotopik araştırmalar gibi ileri düzey analizlerle, karasal çamur volkanlarının oluşumu, yapısı ve mikrobiyal çeşitliliği daha anlaşılır olabilecektir.

Anahtar Kelimeler

• Arke
• Bakteri
• Çamur volkanı
• Düzce
• Mikrobiyal bolluk

Destekleyen Kurum

Çalışma Dokuz Eylül Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi FHD-2023-3225 koduyla desteklenmiştir.

Proje Numarası

FHD-2023-3225

Etik Beyan

Çalışma, etik kurul izni veya herhangi bir özel izin gerektirmemektedir.

Teşekkür

Bu çalışma Dokuz Eylül Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi FHD-2023-3225 koduyla desteklenmiştir. Proje ekibine ayrıca teşekkür ederiz.

Kaynakça

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