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Öğe Draft Genome Sequence of Staphylococcus felis HARRANVET Strain(2021) Aslantaş, Özkan; Keskin, Oktay; Büyükaltay, Kaan; Yücetepe, Ayfer GüllüStaphylococcus felis is one of staphylococci residing on skin of cats, and has been increasingly reported as a potential facultative pathogen. A recently isolated Staphylococcus felis(named as S. felis HARRANVET strain) from necrotizing fasciitis case of a cat was characterized using wholegenome sequencing (WGS), and assembled genome was in silico screened for putative virulence and antimicrobial resistance genes. The isolate was pan-susceptible to all antimicrobials tested, indicated absence of resistance genes. A limited number of virulence genes associated with adhesion was found. For the first time, in Turkey, the draft genome of Staphylococcus felis was obtained and made publicly accessible.Öğe INVESTIGATION OF THE ANTIBIOTIC RESISTANCE AND BIOFILM FORMATION OF STAPHYLOCOCCUS AUREUS STRAINS ISOLATED FROM GANGRENOUS MASTITIS OF EWES(Akademiai Kiado Zrt, 2012) Tel, Osman Yasar; Aslantas, Ozkan; Keskin, Oktay; Yilmaz, Ebru Sebnem; Demir, CemilIn this study, Staphylococcus aureus strains (n = 110) isolated from seven ewe flocks in Sanliurfa, Turkey were screened for antibiotic resistance and biofilm-forming ability as well as for genes associated with antibiotic resistance and biofilm-forming ability. All isolates were found to be susceptible to oxacillin, gentamicin, clindamycin, cefoxitin, tetracycline, vancomycin, amoxicillin-clavulanic acid, ciprofloxacin and sulphamethoxazole-trimethoprim. The percent proportions of strains resistant to penicillin G, ampicillin and erythromycin were 27.2% (n = 30), 25.4% (n = 28) and 6.3% (n = 7), respectively. Regarding the antibiotic resistance genes, 32 (29%) isolates carried the blaZ and 8 (7.2%) the ermC gene. Other resistance genes were not detected in the isolates. All isolates showed biofilm-forming ability on Congo red agar (CRA), while 108 (98.18%) and 101 (91.81%) of them were identified as biofilm producers by the use of standard tube (ST) and microplate (MP) methods, respectively. All isolates carried the icaA and icaD genes but none of them harboured the bap gene. The results demonstrated that S. aureus isolates from gangrenous mastitis were mainly resistant to penicillins (which are susceptible to the staphylococcal beta-lactamase enzyme), and less frequently to erythromycin. Furthermore, all of the S. aureus isolates produced biofilm which was considered a potential virulence factor in the pathogenesis of staphylococcal mastitis.Öğe Investigation of Toxin Genes of Staphylococcus aureus Strains Isolated from Gangrenous Mastitis in Ewes(Kafkas Univ, Veteriner Fakultesi Dergisi, 2011) Tel, Osman Yasar; Aslantas, Ozkan; Keskin, Oktay; Yilmaz, Ebru Sebnem; Demir, CemilIn this study, it was aimed to determine staphylococcal enterotoxin (SE) genes, toxic shock syndrome toxin (TSST) gene and exfoliative toxin (ET) genes in 110 Staphylococcus aureus strains from gangrenous mastitis cases in seven ewe flocks in Sanliurfa, Turkey. Among investigated isolates, only sec and tst toxin genes were detected. The results of this study showed that the rates of enterotoxin production were high (100%) in S. aureus strains isolated from ovine gangrenous mastitis. Moreover, it was demonstrated that S. aureus causing gangrenous mastitis harboured sec and tst genes suggesting that these genes may have a role in ovine mastitis pathogenesis.Öğe Investigation of toxin genes of staphylococcus aureus strains isolated from gangrenous mastitis in ewes(2011) Tel, Yaşar Osman; Keskin, Oktay; Aslantaş, Özkan; Yılmaz, Şebnem Ebru; Demir, CemilIn this study, it was aimed to determine staphylococcal enterotoxin (SE) genes, toxic shock syndrome toxin (TSST) gene and exfoliative toxin (ET) genes in 110 Staphylococcus aureus strains from gangrenous mastitis cases in seven ewe flocks in Sanliurfa, Turkey. Among investigated isolates, only sec and tst toxin genes were detected. The results of this study showed that the rates of enterotoxin production were high (100%) in S. aureus strains isolated from ovine gangrenous mastitis. Moreover, it was demonstrated that S. aureus causing gangrenous mastitis harboured sec and tst genes suggesting that these genes may have a role in ovine mastitis pathogenesis.Öğe Molecular Characterization of Pseudomonas aeruginosa Isolated From Clinical Bovine Mastitis Cases(Kafkas Univ, Veteriner Fakultesi Dergisi, 2022) Aslantas, Ozkan; Turkyilmaz, Suheyla; Keskin, Oktay; Yucetepe, Ayfer Gullu; Buyukaltay, KaanThis study aimed to investigate the presence and distribution of virulence determinants and their antimicrobial susceptibilities of 44 Pseudomonas aeruginosa isolates obtained from clinical bovine mastitis cases. In addition, selected 6 P. aeruginosa isolates were further characterized using whole-genome sequencing (WGS). Based on the presence of T3SS-related genes, 25% of the isolates were found to carry exoU and/or exoS genes belonging to invasive (exoU-/exoS+, 18.2%) and cytotoxic (exoU+/exoS-, 6.8%) strains. But, none of the isolates carried both exoU and exoS genes. In terms of other virulence genes examined, various virulence gene profiles were observed among the isolates. The majority of the isolates (72.7%) were susceptible to all tested antimicrobials. Resistance rates to ciprofloxacin and carbapenems (imipenem and meropenem) were determined as 25% and 4.5%, respectively. WGS analysis indicated the presence of different resistome, but fosA genes in all isolates, and different combinations of mutations in gyrA, parC, oprD, efflux pump, and genes playing a role in the regulation of ampC gene expression. Different sequence types (STs) and serotypes were found in representative isolates with the occurrence of the O11-ST235 clone, which is a worldwide multidrug-resistant high-risk clone representing a serious public health threat. The findings of this study provide valuable information on P. aeruginosa isolated from clinical bovine mastitis cases and current antimicrobial resistance levels and virulence determinants.Öğe Pathological and Microbiological Investigations of Pneumonic Pasteurellosis in Sheep(Kafkas Univ, Veteriner Fakultesi Dergisi, 2013) Ozyildiz, Zafer; Tel, Osman Yasar; Yilmaz, Rahsan; Ozsoy, Sule Yurdagul; Keskin, OktayIn this study, between March 2010 and March 2011, 110 pneumonia suspected lung tissues were examined histopathologically, immunohistochemically and microbiologically, in Sanliurfa province. After definition of the macroscopic localization of the consolidated areas in the lungs, tissue samples were taken and preserved in cold chain and 10% formalin for microbiological and pathological examinations, respectively. For bacteriological examination of Pasteurella spp. lung specimens were inoculated in 7% sheep blood agar and Mc Conkey agar. After routine pathological tissue follow up procedure, tissues were embedded in paraffin and obtained sections stained with Hematoxylin&Eosin (H&E). The cases, having histopathological findings consistent with pneumonia, were forwarded to immunohistochemical (IHC) examinations to know whether lesions related to Mannheimia haemolytica and Pasteurella multocida using hyperimmune polyclonal rabbit sera in Avidin Biotin Complex Peroxidase (ABC-P). Microbiological, histopathological and immunohistochemical findings were comparatively evaluated in examined animals. Pasteurella multocida as a cause of pneumonia were detected in 38 cases of microbiological inoculations. Immunohistochemical staining resulted Mannheimia haemolytica (n=35) and Pasteurella multocida (n=30) positive. Immunohistochemically both Mannheimia haemolytica and Pasteurella multocida were positive in 23 cases and 45 animals were negative for both bacteria. The aim of this study is to show importance and role of Pasteurella spp, in sheep pneumonia in Sanliurfa region.Öğe Pathological and microbiological investigations of pneumonic Pasteurellosis in sheep(2013) Özyıldız, Zafer; Tel, Osman Yaşar; Yılmaz, Rahşan; Özsoy, Şule Yurdagül; Keskin, OktayBu çalışmada, Şanlıurfa ilinde Mart 2010-Mart 2011 tarihleri arasında, 110 adet pnömoni şüpheli akciğer dokuları histopatolojik immunohistokimyasal ve mikrobiyolojik olarak incelendi. İncelenen akciğerlerde makroskobik olarak konsolide alanların lokalizasyonu belirlendikten sonra bu bölgelerden alınan doku örneklerinin bir kısmı soğuk zincirde muhafaza edilerek mikrobiyolojik inceleme için kullanıldı. Doku örneklerinin bir kısmı %7 lik koyun kanlı agar ve Mc Conkey agara ekildi. Diğer bir kısım ise %10’luk tamponlu formaldehitte tespit edildikten sonra, rutin doku takibinden geçirilip, histopatolojik incelemeler için Hematoksilen&Eozin (H&E) ile boyandı. Histopatolojik olarak pnömoni teşhisi konulan kesitler, poliklonal tavşan Mannheimia haemolytica ve Pasteurella multocida hiperimmun serumları kullanılarak Avidin Biyotin Kompleks Peroksidaz (ABC-P) Yöntemi ile immunohistokimyasal olarak boyandı. İncelenen hayvanlarda mikrobiyolojik, histopatolojik ve immunohistokimyasal bulgular karşılaştırmalı olarak değerlendirildi. Mikrobiyolojik ekimlerde 38 vakada Pasteurella multocida pnömoni etkeni olarak belirlendi. Yapılan immunohistokimyasal boyamalar sonrası toplam 35 hayvanda Mannheimia haemolytica, 30 hayvanda Pasteurella multocida, 23 hayvanda her ikisinin birden ve 45 hayvanda ise nedeni belirlenmeyen farklı etkenlerin pnömoni sebebi olduğu ortaya konuldu. Bu çalışmanın amacı Şanlıurfa İlindeki koyun pnömonilerinde Pasteurella spp.’lerin yeri ve öneminin belirlenmesidir.Öğe Whole-Genome Sequencing-Based Characterization of Listeria monocytogenes from Food and Animal Clinical Cases(Kafkas Univ, Veteriner Fakultesi Dergisi, 2023) Aslantas, Ozkan; Buyukaltay, Kaan; Keskin, Oktay; Gullu Yucetepe, Ayfer; Adiguzel, AdemListeriosis is a rare but severe foodborne infection caused by Listeria monocytogenes. In this study, we performed comparative whole-genome sequencing (WGS) on 28 Listeria monocytogenes from seven invasive listeriosis cases in animals and 21 food samples in Turkiye for the first time. Food isolates were delineated into eleven clonal complexes (CCs), namely CC1, CC2, CC3, CC8, CC9, CC20, CC69, CC124, CC155, CC204, ST3002. The isolates from meningoencephalitis cases were associated with CC1, whereas CC9 and CC7 were associated with the isolates from sheep abortus cases. All the isolates carried the fosX, lin, norB, and sul genes. In addition, emrC (n=15), bcrC (n=4), emrE (n=2), qacA (n=1), cadA (n=5) and cadC (n=1) genes, conferring resistance to stress and disinfectants were detected. Listeria pathogenicity island (LIPI)-1 and LIPI-2 were distributed in all isolates, but LIPI-3 was closely related to CC1, CC3, and ST3002 isolates. LIPI-4 was not found in any of the L. monocytogenes isolates. The Inc18(rep25) and Inc18(rep26) plasmids were found in 16 (57.1%) isolates. A total of 15 different intact prophage genomes ranging from one to three were detected in the genomes of 24 isolates. The hypervirulent CC1 and CC2 clones that pose a significant threat to food safety and public health were detected among food isolates. These findings highlight the importance of continuous surveillance of hypervirulent L. monocytogenes strains in different settings.
