AUTHOR=Shen Wenluan , Yang Na , Teng Da , Hao Ya , Ma Xuanxuan , Mao Ruoyu , Wang Jianhua 

TITLE=Design and High Expression of Non-glycosylated Lysostaphins in Pichia pastoris and Their Pharmacodynamic Study

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.637662

DOI=10.3389/fmicb.2021.637662

ISSN=1664-302X

ABSTRACT=<p>Lysostaphin is an effective antimicrobial agent to <italic>Staphylococcus</italic>, especially for the methicillin-resistant <italic>Staphylococcus aureus</italic> (MRSA) and multidrug-resistant <italic>Staphylococcus aureus</italic> (MDRSA). In this study, the seven lysostaphin derived mutants (rLys) were designed to overcome the barrier of glycosylation during expression in <italic>Pichia pastoris</italic>. Among them, 127A and 127A232Q had highest antimicrobial activity (MIC values 0.07–0.3 μM) to <italic>S. aureus</italic> than others and the commercial lysostaphins (1–15.8 times). There was no glycosylation during the expression in 5-L fermenter level, with the high yield of 1315 mg/L (127A) and 1141 mg/L (127A232Q), respectively. Meanwhile, 127A and 127A232Q effectively killed 99.9% of <italic>S. aureus</italic> at low concentration (1 × MIC) within 30 min, without the regrowth of pathogen. They also showed low toxicity, high pH and temperature stability. The results of <italic>in vivo</italic> therapeutic effect of 127A and 127A232Q against high virulent <italic>S. aureus</italic> CVCC546 showed that 127A and 127A232Q increased the survival rate of infected mice up to 100% at the dose of 10 mg/kg than the untreated group, reduced the bacterial translocation by 5-7 log CFU (over 99%) in organs compared to the untreated group and alleviated multiple-organ injuries (liver, kidney and spleen). These data indicated that the non-glycosylated lysostaphin 127A and 127A232Q may be a promising therapeutic agent against MDR staphylococcal infections.</p>