Iranian Biomedical Journal
مجله بیومدیکال ایران
IBJ
Basic Sciences
http://ibj.pasteur.ac.ir
1
admin
1028-852X
2008-823X
-
10.61882/ibj
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8888
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en
jalali
1401
8
1
gregorian
2022
11
1
26
6
online
1
fulltext
en
Development of Streptococcus equisimilis Group G Mutant Strains with Ability to Produce Low Polydisperse and Low-Molecular-Weight Hyaluronic Acid
Pharmaceutical Biotechnology
Pharmaceutical Biotechnology
مقاله کامل
Full Length/Original Article
<span style="font-family:Times New Roman;"><span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt"><span style="color:black">Background:</span></span></b><span style="font-size:10.5pt"><span style="color:black"> Hyaluronic acid (HA), a natural polymer with wide applications in biomedicine and cosmetics, is mainly produced by <i>Streptococcal</i> fermentation at industrial scale. In the present study, chemical random mutagenesis was used for development of <i>Streptococcus equisimilis</i> group G mutant strains with high HA productivity. </span></span></span></span></span><br>
<span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt"><span style="color:black">Methods:</span></span></b><span style="font-size:10.5pt"><span style="color:black"> The optimum of the pH of culture condition and cultivation time for HA production by wild strain group G were assessed. At first, two rounds of mutation at different concentrations of NTG was used for mutagenesis. Then, the nonhemolytic and hyaluronidase-negative mutants were screened on the blood and HA agar. HA productivity and molecular weight were determined by carbazole assay, agarose gel electrophoresis and specific staining. Moreover, stability of the high producer mutants was evaluated within 10 generations. </span></span></span></span></span><br>
<span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt"><span style="color:black">Results:</span></span></b><span style="font-size:10.5pt"><span style="color:black"> The results showed that the wild-type strain produced </span></span><span style="font-size:10.5pt"><span style="color:black">1241 ± 2.1 </span></span><span style="font-size:10.5pt"><span style="color:black">µg/ml of HA at pH 5.5 and 4 hours of cultivation, while the screened mutants showed a 16.1-45.5% increase in HA production. Two mutant strains, named Gm2-120-21-3 (2470 ± 8.1 µg/ml) and Gm2-120-21-4 (2856 </span></span><span style="font-size:10.5pt"><span style="color:black">± 4.2 </span></span><span style="font-size:10.5pt"><span style="color:black">µg/ml), indicated the highest titer and a consistent production. The molecular weight (Mw) of HA for the mutants was less than 160 kDa, considering as a low Mw HA. </span></span></span></span></span><br>
<b><span style="font-size:10.5pt"><span style="line-height:115%"><span calibri=""><span style="color:black">Conclusion:</span></span></span></span></b><span style="font-size:10.5pt"><span style="line-height:115%"><span calibri=""><span style="color:black"> The mutant strains producing a low polydisperse, as well as low Mw of HA with high titer might be regarded as potential industrial strains for HA production after further safety investigations.</span></span></span></span></span>
Hyaluronic acid, Microbial production, Molecular weight, Mutation, Streptococcus equisimilis
454
462
http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1437-1&slc_lang=en&sid=1
Bahareh
Jafari
b.jafari2016@gmail.com