1.B.1.1.12
High conductance Omp35 (OmpK35; OmpF) porin.  Expression levels are important for beta-lactam/cephalosporin resistance (Bornet et al. 2004).  95% identical to the Klebsiella pneumoniae orthologue, OmpK35 (Taherpour and Hashemi 2013). In K. pneumoniae, colistin-based combination therapy with a carbapenem and/or tigecycline was associated with significantly decreased mortality rates due in part to synergistic induction of porins K35 and K36 (Stein et al. 2015). They influence imipenem susceptibility as well (Wassef et al. 2015). These two porins play roles in conferring carbapenem resistance in K. pneumoniae (Hamzaoui et al. 2018; Ye et al. 2018). Loss of a single porin (OmpK35 or OmpK36 (TC# 1.B.1.1.19) in Klebsiella pneumoniae is paired with reductions in capsule, increased LPS, and up-regulated transcription of compensatory porin genes, but loss of both porins resulted in an increase in capsule production. Loss of OmpK35 alone or dual porin loss was further associated with reduced oxidative burst by macrophages and increased ability of the bacteria to survive phagocytic killing (Brunson et al. 2019).