7th World Congress on Microbiology November 28-29, 2016 Valencia, Spain

P. O. Akinwole is a senior researcher at the University of Alabama, USA

Dissolved organic carbon (DOC) is the largest organic carbon pool in lotic systems. Current paradigms describing terrestrial DOC in streams depict DOC as both an important carbon and energy source for microorganisms and containing large amounts of chemical and biological refractory humic substances. To better evaluate the reliance of stream microorganisms on terrestrial DOC, we produced 13C-labeled DOC by leaching composted 13C-labelled tulip poplar leaves and twigs in soil columns for 3 months and then leaching the soil with water. This process yields 13C-labeled DOC with size and liability fractions approximating stream water DOC. To determine the microbial groups actively using stream water DOC we incubated streambed sediments in recirculating mesocosm chambers amended with 13C-labeled DOC and examined 13C incorporation into microbial phospholipid fatty acids. Prokaryotes comprised 61% of the mesocosm microbial community and consisted of aerobic, facultative anaerobic and anaerobic bacteria while microeukaryotes comprised the remaining 39%. Comparison by principal component analysis of the microbial communities in stream sediments and stream sediments incubated with or without 13C-labeled humic DOC showed our mesocosm-based experimental design was sufficiently robust to investigate the use of 13DOC by sediment microbial communities. After 48 hours of incubation, phospholipid fatty acids i15:0, 16:0, 16:1w9, 18:1w9c, 18:1w7c (aerobic/facultative anaerobic bacterial biomarkers) and 20:4w6, 20:5w3 (microeukaryotic biomarkers) showed increased abundance of 13C. This suggests that the hetero organotrophic bacteria actively utilized the 13DOC and that microeukaryotic predators consumed those bacteria. These findings indicate that DOC, although generally considered refractory and poorly utilized by microbiota, substantially contributes to the energy and carbon flow in aquatic ecosystems.

Sahar Essa works at the Department of Microbiology, Faculty of Medicine at the Kuwait University

Introduction: Hepatitis C virus (HCV) is a life threatening human pathogen. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. Clearance of the virus is characterized by a vigorous, persistent T-cell response. Standard treatment involves a combination of pegylated interferon-α (PEG-IFN) and ribavirin, Mechanisms for the observed synergistic effects of the two drugs are still not well understood, but in addition to direct antiviral mechanisms, immunomodulatory effects of both drugs seem to be important with a possible shift from Th2 to Th1 cytokine profiles in successfully treated patients.\r\n\r\nMethod: This study will determine Th1 and Th2 cytokine responses to infection with the major HCV genotypes, before, during and after treatment with PEG-IFN and ribavirin. The proliferative response of peripheral blood mononuclear cells to mitogen will be assessed by measuring uptake of radioactive thymidine and the production of Th1 type and Th2 type cytokines by ELISA.\r\n\r\nResults: We have inducted a total of 36 patients (27 responders and 9 non-responders). There were a significant increase in the levels of Th1 type cytokines IFN, IL-17A and IL-17F between responders and non-responders. IL-4 and IL-6 anti-inflammatory Th2 cytokines is produced at significantly higher levels in non-responders. The ratios involving IFN and IL-4 showed interesting differences. At baseline measurement, IFN/IL-4 and IFN/IL-10 ratios were 18 and 10 fold higher in responders. Likewise, at the end of the treatment, IFN/IL-4, IFN/IL-6 and IFN/IL-10 ratios were 90, 80 and 50 fold respectively higher in responders as compared to non-responders.\r\n\r\nConclusion: Our data suggests that, Th1 biased reactivity and poor Th2 response state appears to be associated with drug effectiveness. In other words, we suggest that the host cytokine profile can either dampen or aid the immune viral response to recent and future drug therapy.\r\n

Dr Young Ah Kim works at the Department of Laboratory Medicine, National Health Insurance Service Ilsan Hospital in South Korea.

Background: The community associated infections due to extended spectrum β lactamase (ESBL) producing Escherichia coli has been well known clinical problems. Serogroup O25-multilocus sequence typing (MLST) sequence type ST131 E. coli has been known as a major clone for worldwide spread because of its multidrug resistances and higher virulence traits.\r\n \r\nMethods: The recent extent and significance of community associated infections caused by ESBL producing E. coli were evaluated by a prospective observational study. We collected non-duplicated E. coli isolates, isolated from consecutive, sequentially encountered patients with community onset episodes (either outpatients or within 48 hours of admission) between March and April 2016 in two community hospital in Gyeonggi province, Korea. Sites of acquisition of the organisms (community associated or healthcare associated), antimicrobial susceptibility and PCR of O25/O16 genes to screen global epidemic ST131were evaluated.\r\n\r\nResults: Of 213 patients infected or colonized with E. coli as outpatients or within 48 hours of hospitalization, 119 (55.9%) had community associated infection (65.5% of which represented urinary tract infection), while the remainder had healthcare associated infection. Of the community associated infections, 26.9% (32/119) were caused by the globally epidemic ST131 strain (25/119 for O25-131 and 7/119 for O16-ST131 respectively). ESBL production was confirmed by phenotypic methods in 24.4% (29/119) of the community associated infections.\r\n\r\nConclusions: A considerable portion of community onset, ESBL producing E. coli infections now occur among patients in Gyeonggi Province, Korea. Increase of ST131 E. coli infections in community without healthcare associated risk factors could be worrisome public health threats.\r\n

Tea Koiava has graduated from Batumi Shota Rustaveli State University in 2007 with a Master’s degree in Genetics. Since 2007, she has been working at Batumi Shota Rustaveli State University as a Chief Specialist of the Department. She is actively engaged in medical/educational and many other kinds of measures taking place at University and leading training courses in Biology as well. She is also engaged in scientific activities of the Department. She is the author of five scientific papers. She is currently pursuing her PhD in Biology Educational Program, specializing in Microbiology.

Background: In the previous years, CTX-M extended spectrum β-lactamases (ESBLs) have emerged worldwide and have replaced classical TEM and SHV-type ESBLs in many countries. CTX-M-15 is currently the most frequent, with a pandemic distribution, and the rapid spread is facilitated by incorporation of resistance genes in mobile genetic elements. This successful ESBL in Gram negative bacteria is closely associated with nosocomial environments and as an intestinal colonized, particularly in old and dependent patients. Little is known about the CTX-M ESBLs among Klebsiella pneumonia in Adjara. Our goal is the detection and characterization of ESBLs among Klebsiella pneumonia isolates from patients in two different hospitals in Adjara.\r\n\r\nMaterial & Methods: Susceptibility profile and identification of the infection of Klebsiella pneumonia (n=23) isolates collected from different hospital services (2013-2015) were performed by disc diffusion methods according to the CLSI guidelines and API 20E, respectively. ESBL producers were detected and/or confirmed by the double disk synergy test using oximino-β-lactamic antibiotics with and without clavulanic acid. Genes of families’ blaTEM, blaOXA, blaSHV and blaCTX-M group 1 were investigated by PCR. Sequencing was performed using group specific primers for CTX-M group 1.\r\n\r\nResults: Fourteen Klebsiella pneumonia producing CTX-M group 1 ESBL infection isolates were detected in different biological samples, namely in sputum (n=8), urine (n=5) and abdominal fluid (n=1), collected in different hospital services. The infection isolates showed an extended resistance profile to aminoglycosides, fluoroquinolones and tetracycline. CTX-M group 1 ESBL isolates showed specific amplification for blaTEM, blaOXA and blaSHV families.\r\n\r\nConclusion: This is the first report of CTX-M group 1 in infection Klebsiella pneumonia isolates in Adjara. This situation might represent the spread of these multidrug resistant Gram negative in acute care hospital in Adjara. The implementation and/or reinforcement of infection control measures, active antibiotic resistance surveillance and colonization screening of high risk patients is important in order to limit the dissemination of CTX-M ESBL producing Klebsiella pneumonia in health care institutions and to the people of Georgia. Colonization screening in elderly and/or dependent patients, upon admission at different health care institutions and their evaluation before discharge are extremely important to prevent the spread of cycle of multidrug resistant Klebsiella pneumonia in various healthcare facilities.\r\n

Hyun-Duck Kim has obtained his Doctor of Dental Surgery and PhD for Public Health Dentistry from Seoul National University School of Dentistry. He has worked as a Visiting Scientist in the Department of Oral health Policy and Epidemiology, Harvard School of Dental Medicine in 1998-1999 and 2006-2007 and in the Department of Periodontology, UNC in 2000. Currently, he is a tenure-track Professor in the Department of Preventive and Social Dentistry, SNU SOD. He has serviced as Vice-Dean during 2010-2011 and the Chairman of the Department of Preventive and Social Dentistry during 2012-2013. He has published and presented more than 200 topics, papers and books.

Subgingival microorganisms could be associated with cardiovascular disease and no study has analyzed the subgingival microbiota according to subclinical atherosclerosis (SA). This study aims to investigate subgingival microbiota related to SA by next generation sequencing (NGS) among Korean adults. From the Yangpyeong cardiovascular cohort, 15 SA cases 15 controls (mean age of 65 years), matched for age, sex and smoking history by 1:1 ratio, recruited in this cross sectional study. SA was assessed by carotid intima-media thickness. SA was defined as Carotid intima-media thickness ≥0.754. Gingival crevicular fluid (subgingival plaque) was sampled from the gingival sulcus of the tooth with the most severe alveolar bone loss. For NGS, 16S rRNA genes from bacteria in subgingival plaque were pyrosequenced. Mann-Whitney test and Chi-square test were performed to assess the association between percentage amount and prevalence of microorganisms and SA, respectively. A total of 926 operational taxon units (OTUs) were pyrosequenced. In terms of percentage amount of OTU, 19 species showed difference between cases and controls. Among them, five species such as EU335295, Capnocytophaga leadbetteri, Oral014, EU150278 and AF385506 were higher in SA. In terms of prevalence of OUT, five species showed difference between cases and controls and Oral014 was high in SA. Five subgingival microorganisms, especially Oral014_s, were associated with SA. Further main studies are needed to rectify our results.

Finger Sebastian is a researcher at the Universidad San Sebastian

Currently the obtaining natural pigments from microorganisms is of interest because they can potentially be used as natural dyes in the food, cosmetics, and textile industries.\r\nIn this study, a blue pigment producing bacteria was isolated and identified, and its chemicals properties were characterized after being purified. The bacterial strain was isolated from a sample of water from Lake Chungará (Chile) for its ability to produce pigment around the colony. Taxonomic identification was based on the sequencing of the 16S rRNA gene. Pigment extraction was performed from a 24 h culture in TYES broth (25°C/150rpm), which was tangentially filtered to obtain a free cell solution. The pigment present in the solution was purified by column chromatography/solid phase extraction in the following resins sequentially: Amberlite XAD, anionic (QMA), C-18, anionic, size exclusion, and finally C-18. The resulting solution was rotary evaporated and crystallized with ethanol. Then, the pigment was analysed by reverse phase (C-18) HPLC-DAD.\r\nThe strain was identified as Arthrobacter sp (99% similarity). Crude pigment production reached 1 g L-1 of culture. The pigment corresponds to a hygroscopic solid of ionic character, very soluble in water, partially soluble in methanol, and insoluble in the other organic solvents. The pigment is more stable between pH 6 and 10 and at temperatures below 60°C. HPLC analysis shows that crude pigment is composed of four major blue compounds with tr min-1 (max nm-1) = 22.06 (603), 22.47 (593), 22.94 (596) and 23.45 (590), and at least four other minor colored compounds. The physicochemical properties and microorganism genus suggest that the compounds belong to the family of azaquinones, chemically related to the bacterial pigment indochrome and amylocyanin. The mentioned pigments were not studied in terms of toxicity or possible applications, which is our future work.