A Review of Secretion Systems in Pathogenic and Non-Pathogenic Bacteria

Abstract

Secretion is an essential duty for prokaryotes to better interact with their surroundings or host. In particular, the production of extracellular proteins and peptides is important in many aspects of survival and organism adaptation to its ecological niche. Secretion systems in bacteria are multi component protein structures used to transport molecules across bacterial membranes. Secretion systems are usually classified into 7 groups: Type I, II, III, IV, V, VI, VI and chaperons navigating the pathways are also a part of the system. Since this systems can transport a variety of different pathogenic factors outside of the bacterial cell and establish the ability to communicate with the environment in which the bacteria live. This is important about the human pathogenic bacteria because by understanding the components and functions of these protein transport systems, we can find the right solution to deal with them. Furthermore, these systems can be used for biological fights.

Comprehensive genome sequence analysis of Ralstonia solanacearum gd-2, a phylotype I sequevar 15 strain collected from a tobacco bacterial phytopathogen

“…T1SS, T2SS, T3SS, T5SS, and T6SS are mainly found in gram-negative bacteria, while T7SS is mainly found in gram-positive bacteria. T4SS is found in both gram-positive and gram-negative bacteria ( Parizad et al, 2016 ; Cordsmeier et al, 2022 ). T1SS and T5SS contain simple structure, consisting of only two or three proteins ( Zhou et al, 2019 ).…”

Photobacterium arenosum WH24, Isolated from the Gill of Pacific Oyster Crassostrea gigas from the North Sea of Germany: Co-cultivation and Prediction of Virulence

“…The OrthoANIu algorithm [ 48 ] ( https://www.ezbiocloud.net/tools/ani ) was used to determine the average nucleotide identity (ANI) genome size and guanine and cytosine (G + C) content. The RAST algorithm v1.073 from the KBase database https://narrative.kbase.us/ genes (The genome features were functionally annotated using the following algorithms: Kmers V2; Kmers V1; protein similarity [ 49 ]) was applied to genome mining and annotated all following genes: the light-emission-involved genes-related Quorum sensing and bacterial luciferase and other important genes like lux R, lux I, lux A, lux B, lux C, lux D, lux E, lux F, lux G, lux O (Regulatory protein), lux S, ssp A, mrc A, pnp , rib D, lum P, mia A, thy A, mdh , pls X, lum Q, suc A, aph A, cqs A, cqs S, lux S, rib E [ 11 , 12 ] and also the important genes involved in virulence of Photobacterium sp included Type I to Type VI secretion systems (T1SS-T6SS) like Imp A, t ss B ( Imp B/ vip A), tss C ( Imp C/ vip B), tss E, tss F ( Imp G/ vas A), tss G ( Imp H/v as B), tss M ( Icm F/v as K), tss J ( vas D), tss K ( Imp J/v as E), tss L ( Imp K/ vas F), clp V ( tss H), Imp I/ Vas C, vas H, hcp , lap P, lap L, secreted agglutinin ( rtx ), plp D, tps B family, rst A- rst B, pdp , vsc D, vcr D, par AB, trac , frp A, tra F [ 15 , 50 , 51 ].…”

“…Despite extensive study and significant progress in understanding secretion systems, the method and the structural and molecular mechanisms of these systems remain unknown. Specific secretion systems are a prerequisite for quorum sensing, so it is even more important to understand their individual components and how they work [ 15 ]. Type I to Type VI secretion systems (T1SS-T6SS) are known in Gram-negative bacteria.…”

“…These systems deliver the molecules they transport directly into the extracellular space without passing the periplasm. In two-stage secretion systems like II and V, proteins enter periplasm space with the aid of general secretion systems like Tat and Sec to find the appropriate folding and then find their way out via one of the two-stage secretion systems in the second phase [ 15 ].…”

Soluble versions of outer membrane cytochromes function as exporters for heterologously produced cargo proteins

“…In general, one has to distinguish between one-step and two-step export machineries. One-step export machineries transport unfolded or partially folded proteins directly from the cytosol to the medium, which requires that the protein has to fold correctly without accessory proteins like foldases or chaperons [18, 28]. Hence, the production of proteins containing cofactors is a challenge using one-step machineries.…”