scholarly journals ISOLATION AND SCREENING OF PROTEOLYTIC BACTERIA FROM SIDOARJO SHRIMP PASTE AS PROTEASE SOURCE TO EXTRACT THE COLLAGEN FROM MILKFISH SCALES (CHANOS CHANOS)

2021 ◽  
Vol 84 (1) ◽  
pp. 211-218
Author(s):  
A Evi Susanti ◽  
Suharti Suharti ◽  
Roswanira Wahab ◽  
Naharotul Chusniyah ◽  
Shindy Tirta Paramitha

This research aimed to isolate protease-producing bacteria from Sidoarjo shrimp paste for extracting collagen from milkfish scales. This study began with isolation, followed by screening and purification of protease-producing bacterial isolates. Further confirmation of the isolates’ proteolytic indices and the crude protease production, the enzymes’ efficacy in extracting collagen from milkfish scales were tested, followed by pathogenicity and identification using 16S rRNA molecular technique. The study has successfully isolated 15 proteolytic bacterial isolates using skimmed milk agar, but only isolates of TR-10, TR-4.1.1, and TR-15.1 exhibited prospective proteolytic activity based on their corresponding proteolytic indices of 2.96 ± 0.06, 3.10 ± 0.10, and 3.71 ± 0.48. Although the proteolytic activity of isolates TR-10 (0.22 ± 0.05 U/mL) and TR-15.1 (1.07 ± 0.14 U/mL) was high in a salt medium using peptone as the nitrogen source, only the former showed satisfactory activity to extract soluble collagen from milkfish scales. Based on the 16SrRNA, the TR-10 isolate was identified as Bacillus megaterium. The non-pathogenicity of the TR-10 bacterium signified its promising role as a protease source for the halal collagen extraction from milkfish scales.

Exopolysaccharides (EPSs) are polymers with large molecular weight that consist of various residues of sugar. These are desired because the substitution of synthetic polymers is degradable and non-toxic. Most microorganisms have the ability to synthesize and excrete exo polysaccharides with new chemical compositions, characteristics and structures in order to have important applications in various areas. The current study based on marine bacterial isolates screening the production of exo polysaccharide. Among the four exopolysaccharide producing isolates, the isolate PMSS12 had the highest production of exo polysaccharides. The efficient marine bacterial isolate PMSS12 was further identified by sequence of 16S rRNA. The PMSS12 isolate was confirmed as Bacillus megaterium. Then the exopolysaccharide produced by Bacillus megaterium was characterized by using FTIR, NMR and SEM.


2021 ◽  
Author(s):  
Asma Ben Salem ◽  
Hanene Chaabane ◽  
Tesnime Ghazouani ◽  
Pierluigi Caboni ◽  
Valentina Coroneo ◽  
...  

Abstract Important mineralization of 14C-chlorpyrifos was found in a Tunisian soil exposed repeatedly to this insecticide. A bacterial strain able to grow in minimal salt medium (MSM) supplemented with 25 mg L− 1 of chlorpyrifos was isolated from this soil. It was characterized as Serratia rubidaea strain ABS 10 using morphological and biochemical analyses, as well as 16S rRNA sequencing. In liquid culture S. rubidaea stain ABS 10 was able to almost entirely dissipate chlorpyrifos within 48 hours of incubation. Although, S. rubidaea strain ABS 10 was able to grow on MSM supplemented with chlorpyrifos and to dissipate it in liquid culture, it was not able to mineralize 14C-chlorpyrifos. Therefore, one can conclude that the dissipation capability of this bacteria might be attributed to its capacity to adsorb CHL. In both non-sterile and sterile soil inoculated with S. rubidaea strain ABS 10, chlorpyrifos was more rapidly dissipated than in respective controls.


Author(s):  
O. Aleruchi ◽  
O. Obire

This investigation focuses on molecular identification of antibiotic resistant bacteria isolated from petroleum producing vicinity using 16S rRNA sequencing based technique. The bacterial 16s rRNA gene sequences were amplified using polymerase chain reaction, sequenced,  characterized and compared by using primers which has been compared to national center for biotechnology information (NCBI) sequence database. The presence of the plasmid mediated antibiotic resistance determinants CTX-M and QNRB genes in the bacterial isolates were analyzed. A total of four bacterial isolates that were resistant to all the antibiotic agents used were identified molecularly. The BLAST results showed 100 % similarity and phylogenetic study indicated that the genes were evolutionarily related to Morganella morganii, Pseudomonas xiamenensis, Chryseobacterium cucumeris and Staphylococcus sp., respectively. The genes obtained were submitted to the NCBI gene bank and were assigned accession number; MN094330, MN094331, MN094332 and MN094333, respectively. CTX-M and QNRB genes were however absent in the bacterial isolates. The result identified some peculiar abilities of the bacterial isolates to be resistant to antibiotics and suggests a correlation with resistance and hydrocarbon utilizing bacteria. The level of resistance could be as a result of the disinfection process during wastewater treatment procedure or the same adaptive mechanisms possessed by the isolates to control the hydrocarbon concentration in their cell. The study also clearly indicates that these wastewaters, when discharged into the environment directly may pose a risk for the spread of antibiotic resistant bacteria.


2014 ◽  
Vol 8 (10) ◽  
pp. 1252-1258 ◽  
Author(s):  
Reem Mostafa Hassan ◽  
Mervat G El Enany ◽  
Hussien H Rizk

Introduction: Diagnosis of bloodstream infections using bacteriological cultures suffers from low sensitivity and reporting delay. Advanced molecular techniques introduced in many laboratories provide rapid results and may show improvements in patient outcomes. This study aimed to evaluate the usefulness of a molecular technique, broad-range 16S rRNA PCR followed by sequencing for the diagnosis of bloodstream infections, compared to blood culture in different patient groups. Methodology: Conventional PCR was performed, using broad-range 16S rRNA primers, on blood cultures collected from different patients with suspected bloodstream infections; results were compared with those of blood culture. Results: Though blood culture is regarded as the gold standard, PCR evaluation showed sensitivity of 86.25%, specificity of 91.25%, positive predictive value of 76.67%, negative predictive value of 95.22%, and accuracy of 88.8%. Conclusions: Molecular assays seem not to be sufficient to replace microbial cultures in the diagnosis of bloodstream infections, but they can offer a rapid, good negative test to rule out infection due to their high negative predictive value.


2009 ◽  
Vol 75 (21) ◽  
pp. 6924-6928 ◽  
Author(s):  
Pathmalal M. Manage ◽  
Christine Edwards ◽  
Brajesh K. Singh ◽  
Linda A. Lawton

ABSTRACT Of 31 freshwater bacterial isolates screened using the Biolog MT2 assay to determine their metabolism of the microcystin LR, 10 were positive. Phylogenetic analysis (16S rRNA) identified them as Arthrobacter spp., Brevibacterium sp., and Rhodococcus sp. This is the first report of microcystin degraders that do not belong to the Proteobacteria.


2010 ◽  
Vol 76 (8) ◽  
pp. 2673-2677 ◽  
Author(s):  
Larissa C. Parsley ◽  
Erin J. Consuegra ◽  
Stephen J. Thomas ◽  
Jaysheel Bhavsar ◽  
Andrew M. Land ◽  
...  

ABSTRACT The viral metagenome within an activated sludge microbial assemblage was sampled using culture-dependent and culture-independent methods and compared to the diversity of activated sludge bacterial taxa. A total of 70 unique cultured bacterial isolates, 24 cultured bacteriophages, 829 bacterial metagenomic clones of 16S rRNA genes, and 1,161 viral metagenomic clones were subjected to a phylogenetic analysis.


Microbiology ◽  
2006 ◽  
Vol 152 (1) ◽  
pp. 29-42 ◽  
Author(s):  
Bláithín Maunsell ◽  
Claire Adams ◽  
Fergal O'Gara

In the soil bacterium Pseudomonas fluorescens M114, extracellular proteolytic activity and fluorescent siderophore (pseudobactin M114) production were previously shown to be co-ordinately negatively regulated in response to environmental iron levels. An iron-starvation extracytoplasmic function sigma factor, PbrA, required for the transcription of siderophore biosynthetic genes, was also implicated in M114 protease regulation. The current study centred on the characterization and genetic regulation of the gene(s) responsible for protease production in M114. A serralysin-type metalloprotease gene, aprA, was identified and found to encode the major, if not only, extracellular protease produced by this strain. The expression of aprA and its protein product were found to be subject to complex regulation. Transcription analysis confirmed that PbrA was required for full aprA transcription under low iron conditions, while the ferric uptake regulator, Fur, was implicated in aprA repression under high iron conditions. Interestingly, the iron regulation of AprA was dependent on culture conditions, with PbrA-independent AprA-mediated proteolytic activity observed on skim milk agar supplemented with yeast extract, when supplied with iron or purified pseudobactin M114. These effects were not observed on skim milk agar without yeast extract. PbrA-independent aprA expression was also observed from a truncated transcriptional fusion when grown in sucrose asparagine tryptone broth supplied with iron or purified pseudobactin M114. Thus, experimental evidence suggested that iron mediated its effects via transcriptional activation by PbrA under low iron conditions, while an as-yet-unidentified sigma factor(s) may be required for the PbrA-independent aprA expression and AprA proteolytic activity induced by siderophore and iron.


2006 ◽  
Vol 4 (4) ◽  
pp. 32-37
Author(s):  
Elisaveta V Korostik ◽  
Alexander G Pinaev ◽  
Gulnar A Akhtemova ◽  
Evgeniy E Andronov

New universal 16S rRNa primers were constructed and tested. These primers allow identifying correct taxonomic position of bacterial isolates and were shown to be useful in microbial community studies. The primers enable to detect the vast majority of unique 16S rRNa gene sequences. In the study 160 restriction types were found in 16S rRNa clone library (190 clones).


Sign in / Sign up

Export Citation Format

Share Document