Bacterial Degradation of N,N-Diethyl-m-Toluamide (DEET): Cloning and Heterologous Expression of DEET Hydrolase

ABSTRACT Pseudomonas putida DTB grew aerobically with N,N-diethyl-m-toluamide (DEET) as a sole carbon source, initially breaking it down into 3-methylbenzoate and diethylamine. The former was further metabolized via 3-methylcatechol and meta ring cleavage. A gene from DTB, dthA, was heterologously expressed and shown to encode the ability to hydrolyze DEET into 3-methylbenzoate and diethylamine.

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Studies on poly-3-hydroxyoctanoate biosynthesis by a consortium of microorganisms

Ovidius University Annals of Chemistry ◽

10.1515/auoc-2016-0009 ◽

2016 ◽

Vol 27 (1) ◽

pp. 44-47 ◽

Cited By ~ 1

Author(s):

Mihaela Carmen Eremia ◽

Irina Lupescu ◽

Mariana Vladu ◽

Maria Petrescu ◽

Gabriela Savoiu ◽

...

Keyword(s):

Bacillus Subtilis ◽

Carbon Source ◽

Pseudomonas Putida ◽

Sole Carbon Source ◽

Bacterial Biomass ◽

Fermentation Medium ◽

Energy Reserve ◽

Bacterial Strains ◽

Sodium Octanoate ◽

Intracellular Energy

Abstract Polyhydroxyalcanoates (PHAs) are specifically produced by a wide variety of bacteria, as an intracellular energy reserve in the form of homo- and copolymers of [R]-β-hydroxyalkanoic acids, depending on the C source used for microorganism growth, when the cells are grown under stressing conditions. In this paper we present microbiological accumulation of poly-3-hydroxyoctanoate (PHO) by using a consortium of bacterial strains, Pseudomonas putida and Bacillus subtilis, in a rate of 3:1, grown on a fermentation medium based on sodium octanoate as the sole carbon source. The experiments performed in the above mentioned conditions led to the following results: from 18.70 g sodium octanoate (7.72 g/L in the fermentation medium) used up during the bioprocess, 3.93-3.96 g/L dry bacterial biomass and 1.834 - 1.884 g/L PHA, containing 85.83 - 86.8% PHO, were obtained.

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Host engineering for improved valerolactam production in Pseudomonas putida

10.1101/660795 ◽

2019 ◽

Cited By ~ 2

Author(s):

Mitchell G. Thompson ◽

Luis E. Valencia ◽

Jacquelyn M. Blake-Hedges ◽

Pablo Cruz-Morales ◽

Alexandria E. Velasquez ◽

...

Keyword(s):

Metabolic Engineering ◽

Carbon Source ◽

Pseudomonas Putida ◽

Aromatic Compounds ◽

Sole Carbon Source ◽

Carbon Sources ◽

Shotgun Proteomics ◽

Rich Media ◽

Amide Hydrolase

ABSTRACTPseudomonas putida is a promising bacterial chassis for metabolic engineering given its ability to metabolize a wide array of carbon sources, especially aromatic compounds derived from lignin. However, this omnivorous metabolism can also be a hindrance when it can naturally metabolize products produced from engineered pathways. Herein we show that P. putida is able to use valerolactam as a sole carbon source, as well as degrade caprolactam. Lactams represent important nylon precursors, and are produced in quantities exceeding one million tons per year[1]. To better understand this metabolism we use a combination of Random Barcode Transposon Sequencing (RB-TnSeq) and shotgun proteomics to identify the oplBA locus as the likely responsible amide hydrolase that initiates valerolactam catabolism. Deletion of the oplBA genes prevented P. putida from growing on valerolactam, prevented the degradation of valerolactam in rich media, and dramatically reduced caprolactam degradation under the same conditions. Deletion of oplBA, as well as pathways that compete for precursors L-lysine or 5-aminovalerate, increased the titer of valerolactam from undetectable after 48 hours of production to ~90 mg/L. This work may serve as a template to rapidly eliminate undesirable metabolism in non-model hosts in future metabolic engineering efforts.

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Engineering of Quasi-Natural Pseudomonas putida Strains for Toluene Metabolism through anortho-Cleavage Degradation Pathway

Applied and Environmental Microbiology ◽

10.1128/aem.64.2.748-751.1998 ◽

1998 ◽

Vol 64 (2) ◽

pp. 748-751 ◽

Cited By ~ 39

Author(s):

Sven Panke ◽

Juan M. Sánchez-Romero ◽

Víctor de Lorenzo

Keyword(s):

Carbon Source ◽

Pseudomonas Putida ◽

Single Gene ◽

Regulatory Gene ◽

Gene Cassette ◽

Degradation Pathway ◽

Ring Cleavage ◽

Step Process ◽

Natural Strain ◽

Genetic Technique

ABSTRACT To construct a bacterial catalyst for bioconversion of toluene and several alkyl and chloro- and nitro-substituted derivatives into the corresponding benzoates, the upper TOL operon of plasmid pWW0 ofPseudomonas putida was fully reassembled as a single gene cassette along with its cognate regulatory gene, xylR. The corresponding DNA segment was then targeted to the chromosome of aP. putida strain by using a genetic technique that allows deletion of all recombinant tags inherited from previous cloning steps and leaves the otherwise natural strain bearing exclusively the DNA segment encoding the phenotype of interest. The resulting strains grew on toluene as the only carbon source through a two-step process: conversion of toluene into benzoate, mediated by the upper TOL enzymes, and further metabolism of benzoate through the housekeepingortho-ring cleavage pathway of the catechol intermediate.

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Biosurfactant Production By A New Pseudomonas Putida Strain

Zeitschrift für Naturforschung C ◽

10.1515/znc-2002-3-426 ◽

2002 ◽

Vol 57 (3-4) ◽

pp. 356-360 ◽

Cited By ~ 88

Author(s):

Borjana K. Tuleva ◽

George R. Ivanov ◽

Nelly E. Christova

Keyword(s):

Surface Tension ◽

Carbon Source ◽

Pseudomonas Putida ◽

Sole Carbon Source ◽

Biosurfactant Production ◽

Emulsifying Activity ◽

Pseudomonas Spp ◽

Poorly Soluble ◽

Surface Active

Observation of both tensio-active and emulsifying activities indicated that biosurfactants were produced by the newly isolated and promising strain Pseudomonas putida 21BN. The biosurfactants were identified as rhamnolipids, the amphiphilic surface-active glycolipids usually secreted by Pseudomonas spp. Their production was observed when the strain was grown on soluble substrates, such as glucose or on poorly soluble substrates, such as hexadecane, reaching values of 1.2 g l-1. When grown on hexadecane as the sole carbon source the biosurfactant lowered the surface tension of the medium to 29 mN m-1 and formed stable and compact emulsions with emulsifying activity of 69%

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Bacterial Degradation of 2-Methylisoborneol

Water Science & Technology ◽

10.2166/wst.1988.0244 ◽

1988 ◽

Vol 20 (8-9) ◽

pp. 205-210 ◽

Cited By ~ 10

Author(s):

G. Izaguirre ◽

R. L. Wolfe ◽

E. G. Means

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Carbon Source ◽

Lake Water ◽

Sole Carbon Source ◽

Natural Waters ◽

Bacterial Degradation ◽

Sediment Samples ◽

Water And Sediment ◽

Water And Sediment Samples

2-Methylisoborneol (MIB) is a musty-odored compound occurring in natural waters that is difficult to remove by conventional water treatment methods. Biodegra-dation may be an alternative for its removal from drinking water. Studies were undertaken to determine the conditions enhancing MIB degradation and to isolate and identify the bacteria responsible. MIB degraders were enriched using mg/l levels of the compound, in a defined mineral medium, inoculated with water and sediment samples from reservoirs where MIB is seasonally produced. Cultures that degraded MIB were isolated and enumerated. Degradation occurred only in mixed cultures. MIB supported growth as sole carbon source at 1-6.7 mg/l. MIB at 10 µg/l was also degraded in sterile lake water inoculated with washed bacteria. The degradation of MIB at both µg/l and mg/l levels took from 7 days to more than 2 weeks.

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Identification of genes encoding a novel ABC transporter in Lactobacillus delbrueckii for inulin polymers uptake

Scientific Reports ◽

10.1038/s41598-021-95356-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yuji Tsujikawa ◽

Shu Ishikawa ◽

Iwao Sakane ◽

Ken-ichi Yoshida ◽

Ro Osawa

Keyword(s):

Bacillus Subtilis ◽

Carbon Source ◽

Heterologous Expression ◽

Gene Cluster ◽

Abc Transporter ◽

Transcriptome Analysis ◽

Sole Carbon Source ◽

Cultured Cells ◽

Lactobacillus Delbrueckii ◽

Genes Encoding

AbstractLactobacillus delbrueckii JCM 1002T grows on highly polymerized inulin-type fructans as its sole carbon source. When it was grown on inulin, a > 10 kb long gene cluster inuABCDEF (Ldb1381-1386) encoding a plausible ABC transporter was suggested to be induced, since a transcriptome analysis revealed that the fourth gene inuD (Ldb1384) was up-regulated most prominently. Although Bacillus subtilis 168 is originally unable to utilize inulin, it became to grow on inulin upon heterologous expression of inuABCDEF. When freshly cultured cells of the recombinant B. subtilis were then densely suspended in buffer containing inulin polymers and incubated, inulin gradually disappeared from the buffer and accumulated in the cells without being degraded, whereas levan-type fructans did not disappear. The results imply that inuABCDEF might encode a novel ABC transporter in L. delbrueckii to “monopolize” inulin polymers selectively, thereby, providing a possible advantage in competition with other concomitant inulin-utilizing bacteria.

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