ISOLASI DAN UJI KOMPATIBILITAS BAKTERI HIDROLITIK DARI TANAH TEMPAT PEMROSESAN AKHIR TALANGAGUNG, KABUPATEN MALANG

Talangagung landfill, Malang Regency has used the controlled landfill method. The landfill process produces methane gas that has been flowed as fuel so that it is estimated that there are bacteria with a variety of enzymatic activities that have worked in degrading waste. The purpose of this study was to isolate bacteria from landfill and determine the ability to produce amylase, protease, lipase, and cellulase and test the compatibility of bacteria. The methods used include bacterial isolation using the pour plate method and purification of bacterial isolates using the streak plate method. Bacterial selection is done on selective media containing starch, tributyrin, cellulose, and skim milk. There were 21 bacterial isolates successfully isolated 13 consisting of bacterial isolates showed proteolytic activity, 10 cellulolytic bacteria, 8 amylolytic, and 15 lipolytic. The isolates that show compatible results are BTA 5.7.14, BTA 5.7.7, BTA 5.7.12, and BTA 5.7.6 therefore they can be used as a potential consortium for organic waste recycle.

Epidemiological and Genomic Characterization of Campylobacter jejuni Isolates from a Foodborne Outbreak at Hangzhou, China

Background: Foodborne outbreaks caused by Campylobacter jejuni have become a significant public health problem worldwide. Applying genomic sequencing as a routine part of foodborne outbreak investigation remains in its infancy in China. We applied both traditional PFGE profiling and genomic investigation to understand the cause of a foodborne outbreak in Hangzhou in December 2018. Method: A total of 43 fecal samples, including 27 sick patients and 16 canteen employees from a high school in Hangzhou city in Zhejiang province, were recruited. Routine real-time fluorescent PCR assays were used for scanning the potential infectious agents, including viral pathogens (norovirus, rotavirus, adenovirus, and astrovirus), and bacterial pathogens (Salmonella, Shigella, Campylobacter jejuni, Vibrio parahaemolyticus and Vibrio cholerae). Bacterial selection medium was used to isolate and identify the positive bacteria identified by molecular test. Pulsed field gel electrophoresis (PFGE), and next generation sequencing (NGS) were applied to fifteen recovered C. jejuni isolates to further understand the case linkage of this particular outbreak. Additionally, we retrieved reference genomes from the NCBI database and performed a comparative genomics analysis with the examined genomes produced in this study. Results: The analyzed samples were found to be negative for the queried viruses. Additionally, Salmonella, Shigella, Vibrio parahaemolyticus and Vibrio cholera were not detected. Fifteen C. jejuni strains were identified by the real-time PCR assay and bacterial selection medium. These C. jejuni strains were classified into two genetic profiles defined by the PFGE. Out of fifteen C. jejuni strains, fourteen have a unified consistent genotype belonging to ST2988, and the other strain belongs to ST8149, with a 66.7% similarity in comparison with the rest of the strains. Moreover, all fifteen strains harbored blaOXA-61 and tet(O), in addition to a chromosomal mutation in gyrA (T86I). The examined fourteen strains of ST2988 from CC354 clone group have very minimal genetic difference (3~66 SNPs), demonstrated by the phylogenomic investigation. Conclusion: Both genomic investigation and PFGE profiling confirmed that C. jejuni ST2988, a new derivative from CC354, was responsible for the foodborne outbreak Illustrated in this study.

Isolasi dan Karakteristik Bakteri Pendegradasi Selulosa dari Limbah Pusat Industri Mebel Antang Makassar

<p>Antang Furniture Center in Makassar is one of the wood industries and is still traditionally. The wood processing produces waste containing cellulose that is difficult to degrade. This study aims to isolate and observe the characteristics of cellulose degrading bacteria. This research was conducted at the Microbiology Laboratory, Faculty of Mathematics and Natural Sciences, Hasanuddin University, Makassar from March 2019 to November 2019. The method used was an experimental laboratory consisting of <em>Carboxyl Methyl Cellulose</em> (CMC) media for bacterial selection and characterization including microscopic morphology with Gram staining and morphology macroscopic with colony structure. The results showed that cellulose degrading bacteria were characterized by the formation of clear zones formed on CMC media in petri dishes. Based on macroscopic and microscopic morphological characteristics, eleven types of cellulose degrading bacteria isolates were obtained. The isolates obtained can be a source of bacterial isolates for further application in wood waste or other wastes that contain of cellulose.</p>

Combinatorial design of chemical-dependent protein switches for controlling intracellular electron transfer

ABSTRACTOne challenge with controlling electron flow in cells is the lack of biomolecules that directly couple the sensing of environmental conditions to electron transfer efficiency. To overcome this protein component limitation, we randomly inserted the ligand binding domain (LBD) from the human estrogen receptor (ER) into a thermostable 2Fe-2S ferredoxin (Fd) from Mastigocladus laminosus and used a bacterial selection to identify Fd-LBD fusion proteins that support electron transfer from a Fd-NADP reductase (FNR) to a Fd-dependent sulfite reductase (SIR). Mapping LBD insertion sites onto structure revealed that Fd tolerates domain insertion adjacent to or within the tetracysteine motif that coordinates the 2Fe-2S metallocluster. With both classes of the fusion proteins, cellular ET was enhanced by the ER antagonist 4-hydroxytamoxifen. In addition, one of Fds arising from ER-LBD insertion within the tetracysteine motif acquires an oxygen-tolerant 2Fe-2S cluster, suggesting that ET is regulated through post-translational ligand binding.