BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE

Pınar Şekerci Keleş; Yusuf Esen

TR EN

ARDAHAN DERİ PEYNİRİNDEN İZOLE EDİLEN BAKTERİLERDE BİYOFİLM OLUŞUMU VE VİRÜLANS ÖZELLİKLERİ

Abstract

Standart olmayan koşullar altında üretilen geleneksel peynirler, rutin kalite göstergeleriyle tam olarak yakalanamayan bakteriyel kalıcılık özelliklerini destekleyebilir. Bu çalışma, geleneksel Ardahan Deri peynirinden elde edilen altı bakteri izolatının (P1-P6) biyofilm oluşumunu ve fenotipik ve genotipik virülansla ilişkili özelliklerini karakterize etmiştir. Biyofilm oluşumu, kristal viyole mikrotiter plak testi ile değerlendirilmiş ve OD tabanlı kesme kriterleri kullanılarak kategorize edilmiştir. Tüm izolatlar ölçülebilir biyofilm oluşumu göstermiştir; Enterococcus faecalis (P1) ve Proteus vulgaris (P2) orta düzeyde biyofilm üreticisi olarak sınıflandırılırken, diğer suşlar zayıf üretici olarak belirlenmiştir. Fenotipik virülans taraması, tüm izolatların %5 koyun kanlı agar üzerinde hemolitik aktivite gösterdiğini ortaya koymuştur. DNaz ve jelatinaz aktiviteleri tespit edilmemiş, proteaz aktivitesi ise sadece P. vulgaris'te (P2) gözlemlenmiştir. Enterokok virülans belirleyicilerini hedefleyen PCR taraması, E. faecalis'te (P1) ace ve gelE genlerinin varlığını gösterirken, fenotipik jelatinaz negatif bulunmuş; bu da uygulanan analiz koşulları altında potansiyel genotip-fenotip uyumsuzluk olduğunu göstermiştir. İzolatların gösterdiği heterojen kalıcılık ve virülansla ilişkili özellikler, geleneksel peynir üretim sistemlerinde risk odaklı izleme ve hijyen takviyesinin önemini ortaya koymuştur.

Keywords

BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE

Abstract

Artisanal cheeses produced under non-standardized conditions can support bacterial persistence traits that are not fully captured by routine quality indicators. This study characterized biofilm formation and selected phenotypic and genotypic virulence-associated traits of six bacterial isolates (P1–P6) recovered from artisanal Ardahan Deri cheese. Biofilm formation was assessed by a crystal violet microtiter plate assay and categorized using OD-based cut-off criteria. All isolates showed measurable biofilm formation; Enterococcus faecalis (P1) and Proteus vulgaris (P2) were classified as moderate biofilm producers, whereas the other strains were weak producers. Phenotypic virulence screening revealed hemolytic activity in all isolates on 5% sheep blood agar. DNase and gelatinase activities were not detected, and protease activity was observed only in P. vulgaris (P2). PCR screening targeting enterococcal virulence determinants indicated the presence of ace and gelE in E. faecalis (P1), while phenotypic gelatinase remained negative, supporting potential genotype–phenotype discordance under the applied assay conditions. The isolates displayed heterogeneous persistence- and virulence-associated traits, highlighting the value of risk-oriented monitoring and hygiene reinforcement in artisanal cheese systems.

Keywords

Supporting Institution

There is no funding for this study.

Ethical Statement

This study does not have any parts requiring ethical committee approval.

Thanks

The authors would like to thank Ardahan University Vocational School of Technical Sciences for allowing the Advanced Technologies Laboratory to use.

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Details

Primary Language

English

Subjects

Food Engineering

Journal Section

Research Article

Authors

Pınar Şekerci Keleş
0000-0002-6225-4781
Türkiye

Yusuf Esen ^*
0000-0003-1173-0677
Türkiye

Publication Date

June 3, 2026

Submission Date

January 30, 2026

Acceptance Date

February 25, 2026

Published in Issue

Year 2026 Volume: 29 Number: 2

IZ

https://izlik.org/JA67MD63ZK

Cite

RIS / Bibtex

APA

Şekerci Keleş, P., & Esen, Y. (2026). BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE. Kahramanmaraş Sütçü İmam Üniversitesi Mühendislik Bilimleri Dergisi, 29(2), 797-805. https://izlik.org/JA67MD63ZK

AMA

1.Şekerci Keleş P, Esen Y. BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE. KSU J. Eng. Sci. 2026;29(2):797-805. https://izlik.org/JA67MD63ZK

Chicago

Şekerci Keleş, Pınar, and Yusuf Esen. 2026. “BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE”. Kahramanmaraş Sütçü İmam Üniversitesi Mühendislik Bilimleri Dergisi 29 (2): 797-805. https://izlik.org/JA67MD63ZK.

EndNote

Şekerci Keleş P, Esen Y (June 1, 2026) BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE. Kahramanmaraş Sütçü İmam Üniversitesi Mühendislik Bilimleri Dergisi 29 2 797–805.

IEEE

[1]P. Şekerci Keleş and Y. Esen, “BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE”, KSU J. Eng. Sci., vol. 29, no. 2, pp. 797–805, June 2026, [Online]. Available: https://izlik.org/JA67MD63ZK

ISNAD

Şekerci Keleş, Pınar - Esen, Yusuf. “BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE”. Kahramanmaraş Sütçü İmam Üniversitesi Mühendislik Bilimleri Dergisi 29/2 (June 1, 2026): 797-805. https://izlik.org/JA67MD63ZK.

JAMA

1.Şekerci Keleş P, Esen Y. BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE. KSU J. Eng. Sci. 2026;29:797–805.

MLA

Şekerci Keleş, Pınar, and Yusuf Esen. “BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE”. Kahramanmaraş Sütçü İmam Üniversitesi Mühendislik Bilimleri Dergisi, vol. 29, no. 2, June 2026, pp. 797-05, https://izlik.org/JA67MD63ZK.

Vancouver

1.Pınar Şekerci Keleş, Yusuf Esen. BIOFILM FORMATION AND VIRULENCE-ASSOCIATED TRAITS OF BACTERIAL ISOLATES FROM ARTISANAL ARDAHAN DERİ CHEESE. KSU J. Eng. Sci. [Internet]. 2026 Jun. 1;29(2):797-805. Available from: https://izlik.org/JA67MD63ZK