Open AccessThe apolipoprotein N-acyl transferase Lnt is dispensable for growth in Acinetobacter species
Author(s) -
Celena M. Gwin,
Natalia Prakash,
J Christian Belisario,
Lubaina Haider,
Marlene L. Rosen,
Luis R. Martinez,
Nathan W. Rigel
Publication year - 2018
Publication title -
microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.019
H-Index - 179
eISSN - 1465-2080
pISSN - 1350-0872
DOI - 10.1099/mic.0.000726
Subject(s) - biogenesis , biology , bacterial outer membrane , bacteria , biochemistry , function (biology) , microbiology and biotechnology , gram negative bacteria , apolipoprotein b , acinetobacter , cytoplasm , escherichia coli , antibiotics , cholesterol , gene , genetics
Directing the flow of protein traffic is a critical task faced by all cellular organisms. In Gram-negative bacteria, this traffic includes lipoproteins. Lipoproteins are synthesized as precursors in the cytoplasm and receive their acyl modifications upon export across the inner membrane. The third and final acyl chain is added by Lnt, which until recently was thought to be essential in all Gram-negatives. In this report, we show that Acinetobacter species can also tolerate a complete loss-of-function mutation in lnt. Absence of a fully functional Lnt impairs modification of lipoproteins, increases outer membrane permeability and susceptibility to antibiotics, and alters normal cellular morphology. In addition, we show that loss of lnt triggers a global transcriptional response to this added cellular stress. Taken together, our findings provide new insights on and support the growing revisions to the Gram-negative lipoprotein biogenesis paradigm.