scholarly journals New Ceftriaxone- and Multidrug-Resistant Neisseria gonorrhoeae Strain with a Novel MosaicpenAGene Isolated in Japan

2016 ◽  
Vol 60 (7) ◽  
pp. 4339-4341 ◽  
Author(s):  
Shu-ichi Nakayama ◽  
Ken Shimuta ◽  
Kei-ichi Furubayashi ◽  
Takuya Kawahata ◽  
Magnus Unemo ◽  
...  

ABSTRACTWe have characterized in detail a new ceftriaxone- and multidrug-resistantNeisseria gonorrhoeaestrain (FC428) isolated in Japan in 2015. FC428 differed from previous ceftriaxone-resistant strains and contained a novel mosaicpenAallele encoding a new mosaic penicillin-binding protein 2 (PBP 2). However, the resistance-determining 3′-terminal region ofpenAwas almost identical to the regions of two previously reported ceftriaxone-resistant strains from Australia and Japan, indicating that both ceftriaxone-resistant strains and conserved ceftriaxone resistance-determining PBP 2 regions might spread.

2013 ◽  
Vol 57 (11) ◽  
pp. 5225-5232 ◽  
Author(s):  
Ken Shimuta ◽  
Magnus Unemo ◽  
Shu-ichi Nakayama ◽  
Tomoko Morita-Ishihara ◽  
Misato Dorin ◽  
...  

ABSTRACTIn 2009, the first high-level ceftriaxone-resistantNeisseria gonorrhoeaestrain (H041) was isolated in Kyoto, Japan. The present study describes an intensified surveillance (antimicrobial resistance and molecular typing) ofNeisseria gonorrhoeaeisolates in Kyoto and its neighboring prefecture Osaka, Japan, in 2010 to 2012, which was initiated after the identification of H041. From April 2010 to March 2012, 193N. gonorrhoeaeisolates were collected and the MICs (μg/ml) to six antimicrobials, including ceftriaxone, were determined. All isolates showed susceptibility to ceftriaxone and cefixime (MIC values, <0.5 μg/ml), and spectinomycin. The rates of resistance (intermediate susceptibility) to azithromycin, penicillin G, and ciprofloxacin were 3.6% (19.7%), 24.4% (71.0%), and 78.2% (0.5%), respectively. Multilocus sequence typing (MLST) showed that 40.9%, 19.2%, and 17.1% of isolates belonged to ST1901, ST7359, and ST7363, respectively. Furthermore,N. gonorrhoeaemultiantigen sequence typing (NG-MAST) revealed that 12 (63%) of the 19 isolates with decreased susceptibility to ceftriaxone (MIC > 0.064 μg/ml) were of ST1407. NG-MAST ST1407 was also the most prevalent ST (16.1%; 31 of 193 isolates). In those NG-MAST ST1407 strains, several mosaic typepenAalleles were found, including SF-A type (penicillin binding protein 2 allele XXXIV) and its derivatives. These were confirmed using transformation of thepenAmosaic alleles as critical determinants for enhanced cefixime and ceftriaxone MICs. The intensified surveillance in Kyoto and Osaka, Japan, did not identify any dissemination of the high-level ceftriaxone-resistantN. gonorrhoeaestrain H041, suggesting that H041 might have caused only a sporadic case and has not spread further.


2020 ◽  
Vol 64 (11) ◽  
Author(s):  
Saquib Malik ◽  
Monica Kaminski ◽  
David Landman ◽  
John Quale

ABSTRACT Cefiderocol is a siderophore cephalosporin active against many multidrug-resistant (MDR) Gram-negative pathogens. We examined the resistance mechanisms in 12 Acinetobacter baumannii strains with cefiderocol MICs ranging from ≤0.03 to >32 μg/ml. Cefiderocol resistance could not be explained by β-lactamase activity. Cefiderocol resistance was associated with reduced expression of the siderophore receptor gene pirA. Mutations involving PBP3 may have contributed to resistance in one strain. Additional studies are needed to assess the role of other siderophore receptors.


2017 ◽  
Vol 61 (5) ◽  
Author(s):  
Mark van der Linden ◽  
Julia Otten ◽  
Carina Bergmann ◽  
Cristina Latorre ◽  
Josefina Liñares ◽  
...  

ABSTRACT The identification of commensal streptococci species is an everlasting problem due to their ability to genetically transform. A new challenge in this respect is the recent description of Streptococcus pseudopneumoniae as a new species, which was distinguished from closely related pathogenic S. pneumoniae and commensal S. mitis by a variety of physiological and molecular biological tests. Forty-one atypical S. pneumoniae isolates have been collected at the German National Reference Center for Streptococci (GNRCS). Multilocus sequence typing (MLST) confirmed 35 isolates as the species S. pseudopneumoniae. A comparison with the pbp2x sequences from 120 commensal streptococci isolated from different continents revealed that pbp2x is distinct among penicillin-susceptible S. pseudopneumoniae isolates. Four penicillin-binding protein x (PBPx) alleles of penicillin-sensitive S. mitis account for most of the diverse sequence blocks in resistant S. pseudopneumoniae, S. pneumoniae, and S. mitis, and S. infantis and S. oralis sequences were found in S. pneumoniae from Japan. PBP2x genes of the family of mosaic genes related to pbp2x in the S. pneumoniae clone Spain23F-1 were observed in S. oralis and S. infantis as well, confirming its global distribution. Thirty-eight sites were altered within the PBP2x transpeptidase domains of penicillin-resistant strains, excluding another 37 sites present in the reference genes of sensitive strains. Specific mutational patterns were detected depending on the parental sequence blocks, in agreement with distinct mutational pathways during the development of beta-lactam resistance. The majority of the mutations clustered around the active site, whereas others are likely to affect stability or interactions with the C-terminal domain or partner proteins.


2015 ◽  
Vol 59 (8) ◽  
pp. 5003-5006 ◽  
Author(s):  
Amrita Bharat ◽  
Walter Demczuk ◽  
Irene Martin ◽  
Michael R. Mulvey

ABSTRACTTo characterize the relationship between penicillin-binding protein 2 (PBP2/penA) and susceptibility to extended-spectrum cephalosporins (ESCs) and carbapenem antibiotics, we compared 17 PBP2 variants inNeisseria gonorrhoeae. Nonmosaic and mosaic variants of PBP2 caused decreased susceptibility to ESCs and, to a lesser extent, to carbapenems. An A501P substitution in mosaic XXXIV_A501P conferred decreased susceptibility to ESCs but restored carbapenem susceptibility to wild-type levels. These results could aid the molecular surveillance of antimicrobial resistance to these agents.


Biochemistry ◽  
2014 ◽  
Vol 53 (48) ◽  
pp. 7596-7603 ◽  
Author(s):  
Alena Fedarovich ◽  
Edward Cook ◽  
Joshua Tomberg ◽  
Robert A. Nicholas ◽  
Christopher Davies

2016 ◽  
Vol 60 (7) ◽  
pp. 3934-3941 ◽  
Author(s):  
Liana C. Chan ◽  
Aubre Gilbert ◽  
Li Basuino ◽  
Thaina M. da Costa ◽  
Stephanie M. Hamilton ◽  
...  

ABSTRACTStaphylococcus aureusis an important cause of both hospital- and community-associated methicillin-resistantS. aureus(MRSA) infections worldwide. β-Lactam antibiotics are the drugs of choice to treatS. aureusinfections, but resistance to these and other antibiotics make treatment problematic. High-level β-lactam resistance ofS. aureushas always been attributed to the horizontally acquired penicillin binding protein 2a (PBP 2a) encoded by themecAgene. Here, we show thatS. aureuscan also express high-level resistance to β-lactams, including new-generation broad-spectrum cephalosporins that are active against methicillin-resistant strains, through an uncanonical core genome-encoded penicillin binding protein, PBP 4, a nonessential enzyme previously considered not to be important for staphylococcal β-lactam resistance. Our results show that PBP 4 can mediate high-level resistance to β-lactams.


2002 ◽  
Vol 46 (12) ◽  
pp. 3744-3749 ◽  
Author(s):  
Satoshi Ameyama ◽  
Shoichi Onodera ◽  
Masahiro Takahata ◽  
Shinzaburo Minami ◽  
Nobuko Maki ◽  
...  

ABSTRACT Neisseria gonorrhoeae strains with reduced susceptibility to cefixime (MICs, 0.25 to 0.5 μg/ml) were isolated from male urethritis patients in Tokyo, Japan, in 2000 and 2001. The resistance to cephems including cefixime and penicillin was transferred to a susceptible recipient, N. gonorrhoeae ATCC 19424, by transformation of the penicillin-binding protein 2 gene (penA) that had been amplified by PCR from a strain with reduced susceptibility to cefixime (MIC, 0.5 μg/ml). The sequences of penA in the strains with reduced susceptibilities to cefixime were different from those of other susceptible isolates and did not correspond to the reported N. gonorrhoeae penA gene sequences. Some regions in the transpeptidase-encoding domain in this penA gene were similar to those in the penA genes of Neisseria perflava (N. sicca), Neisseria cinerea, Neisseria flavescens, and Neisseria meningitidis. These results showed that a mosaic-like structure in the penA gene conferred reductions in the levels of susceptibility of N. gonorrhoeae to cephems and penicillin in a manner similar to that found for N. meningitidis and Streptococcus pneumoniae.


mBio ◽  
2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Freda E.-C. Jen ◽  
Margaret R. Ketterer ◽  
Evgeny A. Semchenko ◽  
Christopher J. Day ◽  
Kate L. Seib ◽  
...  

ABSTRACT The lipooligosaccharide (LOS) of Neisseria gonorrhoeae plays key roles in pathogenesis and is composed of multiple possible glycoforms. These glycoforms are generated by the process of phase variation and by differences in the glycosyltransferase gene content of particular strains. LOS glycoforms of N. gonorrhoeae can be terminated with an N-acetylneuraminic acid (Neu5Ac), which imparts resistance to the bactericidal activity of serum. However, N. gonorrhoeae cannot synthesize the CMP-Neu5Ac required for LOS biosynthesis and must acquire it from the host. In contrast, Neisseria meningitidis can synthesize endogenous CMP-Neu5Ac, the donor molecule for Neu5Ac, which is a component of some meningococcal capsule structures. Both species have an almost identical LOS sialyltransferase, Lst, that transfers Neu5Ac from CMP-Neu5Ac to the terminus of LOS. Lst is homologous to the LsgB sialyltransferase of nontypeable Haemophilus influenzae (NTHi). Studies in NTHi have demonstrated that LsgB can transfer keto-deoxyoctanoate (KDO) from CMP-KDO to the terminus of LOS in place of Neu5Ac. Here, we show that Lst can also transfer KDO to LOS in place of Neu5Ac in both N. gonorrhoeae and N. meningitidis. Consistent with access to the pool of CMP-KDO in the cytoplasm, we present data indicating that Lst is localized in the cytoplasm. Lst has previously been reported to be localized on the outer membrane. We also demonstrate that KDO is expressed as a terminal LOS structure in vivo in samples from infected women and further show that the anti-KDO monoclonal antibody 6E4 can mediate opsonophagocytic killing of N. gonorrhoeae. Taken together, these studies indicate that KDO expressed on gonococcal LOS represents a new antigen for the development of vaccines against gonorrhea. IMPORTANCE The emergence of multidrug-resistant N. gonorrhoeae strains that are resistant to available antimicrobials is a current health emergency, and no vaccine is available to prevent gonococcal infection. Lipooligosaccharide (LOS) is one of the major virulence factors of N. gonorrhoeae. The sialic acid N-acetylneuraminic acid (Neu5Ac) is present as the terminal glycan on LOS in N. gonorrhoeae. In this study, we made an unexpected discovery that KDO can be incorporated as the terminal glycan on LOS of N. gonorrhoeae by the alpha-2,3-sialyltransferase Lst. We showed that N. gonorrhoeae express KDO on LOS in vivo and that the KDO-specific monoclonal antibody 6E4 can direct opsonophagocytic killing of N. gonorrhoeae. These data support further development of KDO-LOS structures as vaccine antigens for the prevention of infection by N. gonorrhoeae.


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