Type II Fatty Acid Biosynthesis Is Essential for Plasmodium falciparum Sporozoite Development in the Midgut of Anopheles Mosquitoes

ABSTRACT The prodigious rate at which malaria parasites proliferate during asexual blood-stage replication, midgut sporozoite production, and intrahepatic development creates a substantial requirement for essential nutrients, including fatty acids that likely are necessary for parasite membrane formation. Plasmodium parasites obtain fatty acids either by scavenging from the vertebrate host and mosquito vector or by producing fatty acids de novo via the type two fatty acid biosynthesis pathway (FAS-II). Here, we study the FAS-II pathway in Plasmodium falciparum , the species responsible for the most lethal form of human malaria. Using antibodies, we find that the FAS-II enzyme FabI is expressed in mosquito midgut oocysts and sporozoites as well as liver-stage parasites but not during the blood stages. As expected, FabI colocalizes with the apicoplast-targeted acyl carrier protein, indicating that FabI functions in the apicoplast. We further analyze the FAS-II pathway in Plasmodium falciparum by assessing the functional consequences of deleting fabI and fabB/F . Targeted deletion or disruption of these genes in P. falciparum did not affect asexual blood-stage replication or the generation of midgut oocysts; however, subsequent sporozoite development was abolished. We conclude that the P. falciparum FAS-II pathway is essential for sporozoite development within the midgut oocyst. These findings reveal an important distinction from the rodent Plasmodium parasites P. berghei and P. yoelii , where the FAS-II pathway is known to be required for normal parasite progression through the liver stage but is not required for oocyst development in the Anopheles mosquito midgut.

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In Vivo Roles of Fatty Acid Biosynthesis Enzymes in Biosynthesis of Biotin and α-Lipoic Acid in Corynebacterium glutamicum

Applied and Environmental Microbiology ◽

10.1128/aem.01322-17 ◽

2017 ◽

Vol 83 (19) ◽

Cited By ~ 9

Author(s):

Masato Ikeda ◽

Takashi Nagashima ◽

Eri Nakamura ◽

Ryosuke Kato ◽

Masakazu Ohshita ◽

...

Keyword(s):

Fatty Acid ◽

Lipoic Acid ◽

Fatty Acid Synthase ◽

Fatty Acid Biosynthesis ◽

Physiological Role ◽

Type I ◽

Acid Biosynthesis ◽

Content Type ◽

Fas Ii

ABSTRACT For fatty acid biosynthesis, Corynebacterium glutamicum uses two type I fatty acid synthases (FAS-I), FasA and FasB, in addition to acetyl-coenzyme A (CoA) carboxylase (ACC) consisting of AccBC, AccD1, and AccE. The in vivo roles of the enzymes in supplying precursors for biotin and α-lipoic acid remain unclear. Here, we report genetic evidence demonstrating that the biosynthesis of these cofactors is linked to fatty acid biosynthesis through the FAS-I pathway. For this study, we used wild-type C. glutamicum and its derived biotin vitamer producer BFI-5, which was engineered to express Escherichia coli bioBF and Bacillus subtilis bioI. Disruption of either fasA or fasB in strain BFI-5 led to decreased production of biotin vitamers, whereas its amplification contributed to increased production, with a larger impact of fasA in both cases. Double disruptions of fasA and fasB resulted in no biotin vitamer production. The acc genes showed a positive effect on production when amplified simultaneously. Augmented fatty acid biosynthesis was also reflected in pimelic acid production when carbon flow was blocked at the BioF reaction. These results indicate that carbon flow down the FAS-I pathway is destined for channeling into the biotin biosynthesis pathway, and that FasA in particular has a significant impact on precursor supply. In contrast, fasB disruption resulted in auxotrophy for lipoic acid or its precursor octanoic acid in both wild-type and BFI-5 strains. The phenotypes were fully complemented by plasmid-mediated expression of fasB but not fasA. These results reveal that FasB plays a specific physiological role in lipoic acid biosynthesis in C. glutamicum. IMPORTANCE For the de novo biosynthesis of fatty acids, C. glutamicum exceptionally uses a eukaryotic multifunctional type I fatty acid synthase (FAS-I) system comprising FasA and FasB, in contrast to most bacteria, such as E. coli and B. subtilis, which use an individual nonaggregating type II fatty acid synthase (FAS-II) system. In this study, we reported genetic evidence demonstrating that the FAS-I system is the source of the biotin precursor in vivo in the engineered biotin-prototrophic C. glutamicum strain. This study also uncovered the important physiological role of FasB in lipoic acid biosynthesis. Here, we present an FAS-I enzyme that functions in supplying the lipoic acid precursor, although its biosynthesis has been believed to exclusively depend on FAS-II in organisms. The findings obtained here provide new insights into the metabolic engineering of this industrially important microorganism to produce these compounds effectively.

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Turkish freshwater and marine macrophyte extracts show in vitro antiprotozoal activity and inhibit FabI, a key enzyme of Plasmodium falciparum fatty acid biosynthesis

Phytomedicine ◽

10.1016/j.phymed.2005.10.010 ◽

2006 ◽

Vol 13 (6) ◽

pp. 388-393 ◽

Cited By ~ 46

Author(s):

I. Orhan ◽

B. Sener ◽

T. Atıcı ◽

R. Brun ◽

R. Perozzo ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Fatty Acid ◽

Fatty Acid Biosynthesis ◽

Antiprotozoal Activity ◽

Acid Biosynthesis ◽

Key Enzyme

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The same rat Δ6-desaturase not only acts on 18- but also on 24-carbon fatty acids in very-long-chain polyunsaturated fatty acid biosynthesis

Biochemical Journal ◽

10.1042/bj3640049 ◽

2002 ◽

Vol 364 (1) ◽

pp. 49-55 ◽

Cited By ~ 83

Author(s):

Sabine D'ANDREA ◽

Hervé GUILLOU ◽

Sophie JAN ◽

Daniel CATHELINE ◽

Jean-Noël THIBAULT ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Polyunsaturated Fatty Acid ◽

Unsaturated Fatty Acids ◽

Fatty Acid Biosynthesis ◽

Chain Polyunsaturated Fatty Acid ◽

Acid Biosynthesis ◽

Highly Unsaturated Fatty Acids ◽

Long Chain ◽

Δ6 Desaturase

The recently cloned Δ6-desaturase is known to catalyse the first step in very-long-chain polyunsaturated fatty acid biosynthesis, i.e. the desaturation of linoleic and α-linolenic acids. The hypothesis that this enzyme could also catalyse the terminal desaturation step, i.e. the desaturation of 24-carbon highly unsaturated fatty acids, has never been elucidated. To test this hypothesis, the activity of rat Δ6-desaturase expressed in COS-7 cells was investigated. Recombinant Δ6-desaturase expression was analysed by Western blot, revealing a single band at 45kDa. The putative involvement of this enzyme in the Δ6-desaturation of C24:5n-3 to C24:6n-3 was measured by incubating transfected cells with C22:5n-3. Whereas both transfected and non-transfected COS-7 cells were able to synthesize C24:5n-3 by elongation of C22:5n-3, only cells expressing Δ6-desaturase were also able to produce C24:6n-3. In addition, Δ6-desaturation of [1-14C]C24:5n-3 was assayed invitro in homogenates from COS-7 cells expressing Δ6-desaturase or not, showing that Δ6-desaturase catalyses the conversion of C24:5n-3 to C24:6n-3. Evidence is therefore presented that the same rat Δ6-desaturase catalyses not only the conversion of C18:3n-3 to C18:4n-3, but also the conversion of C24:5n-3 to C24:6n-3. A similar mechanism in the n-6 series is strongly suggested.

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SYNTHESIS OF FATTY ACIDS BY TESTICULAR TISSUE IN VITRO

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y63-142 ◽

1963 ◽

Vol 41 (1) ◽

pp. 1267-1274

Author(s):

Peter F. Hall ◽

Edward E. Nishizawa ◽

Kristen B. Eik-Nes

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Biosynthesis ◽

De Novo ◽

Fatty Acid Fraction ◽

Testicular Tissue ◽

Acid Biosynthesis ◽

Adrenal Tissue ◽

Substrate Fatty Acid

The fatty acids palmitic, palmitoleic, stearic, and oleic have been isolated from rabbit testis and evidence for the synthesis of palmitic and stearic acids de novo from acetate-1-C14is presented. ICSH did not produce demonstrable stimulation of the synthesis of these acids in vitro although the hormone stimulated the production of testosterone-C14by the same tissue. Adrenal tissue was shown to contain palmitic, stearic, and oleic acids, and ACTH did not increase the incorporation of acetate-1-C14into a fatty acid fraction extracted following incubation of adrenal tissue in the presence of this substrate. Fatty acid biosynthesis, therefore, is probably not influenced by the mechanisms by which tropic hormones increase steroid formation.

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Fatty acid biosynthesis revisited: structure elucidation and metabolic engineering

Molecular BioSystems ◽

10.1039/c4mb00443d ◽

2015 ◽

Vol 11 (1) ◽

pp. 38-59 ◽

Cited By ~ 91

Author(s):

Joris Beld ◽

D. John Lee ◽

Michael D. Burkart

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Metabolic Engineering ◽

Structure Elucidation ◽

Fatty Acid Biosynthesis ◽

Acid Biosynthesis ◽

Primary Metabolites ◽

Biosynthetic Machinery

Fatty acids are primary metabolites synthesized by complex, elegant, and essential biosynthetic machinery.

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Thiocarbamate Inhibition of Fatty Acid Biosynthesis in Isolated Spinach Chloroplasts

Weed Science ◽

10.1017/s0043174500052607 ◽

1975 ◽

Vol 23 (2) ◽

pp. 100-104 ◽

Cited By ~ 28

Author(s):

R. E. Wilkinson ◽

A. E. Smith

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Biosynthesis ◽

Spinacia Oleracea ◽

Lipid Synthesis ◽

Metabolic Effects ◽

Acid Biosynthesis ◽

Spinach Chloroplasts ◽

Physiological Range

EPTC (S-ethyl dipropylthiocarbamate) (33μM) and diallate [S-(2,3-dichloroallyl)diisopropylthiocarbamate] (90μM) inhibited the incorporation of 6 mM acetate-2-14C (Ac∗) by 80% and 65%, respectively, and the incorporation of 0.5μM malonate-2-14C (Mal∗) by 32% and 26%, respectively, into the lipids of spinach (Spinacia oleraceaL.) chloroplasts. The inhibition of Ac∗or Mal∗incorporation into lipids was not observed in the presence of excess Ac∗or Mal∗, respectively. Incorporation of palmitate-1-14C and oleate-1-14C into chloroplast lipids was inhibited by EPTC and diallate. Mal∗incorporation into dienoic fatty acids was inhibited by EPTC and diallate. The concentration of EPTC and diallate inhibiting lipid synthesis falls into the physiological range of these herbicides, explains some metabolic effects of these compounds, and fits as the mode of activity of these herbicides.

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Effect of Thiolactomycin on de novo Fatty Acid Biosynthesis in Plants

Zeitschrift für Naturforschung C ◽

10.1515/znc-1990-0537 ◽

1990 ◽

Vol 45 (5) ◽

pp. 518-520 ◽

Cited By ~ 4

Author(s):

Manfred Focke ◽

Andrea Feld ◽

Hartmut K. Lichtenthaler

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Fatty Acid Biosynthesis ◽

De Novo ◽

Fatty Acid Synthetase ◽

Acetate Incorporation ◽

Acid Biosynthesis ◽

Acetyl Coa ◽

Malonyl Coa ◽

Total Fatty Acids

Thiolactomycin was shown to be a potent inhibitor of de novo fatty acid biosynthesis in intact isolated chloroplasts (measured as [14C]acetate incorporation into total fatty acids). In our attempt to further localize the inhibition site we confirmed the inhibition with a fatty acid synthetase preparation, measuring the incorporation of [14C]malonyl-CoA into total fatty acids. From the two proposed enzymic targets of the fatty acid synthetase by thiolactomycin we could exclude the acetyl-CoA: ACP transacetylase. It appears that the inhibition by thiolactomycin occurs on the level of the condensing enzymes, i.e. the 3-oxoacyl-ACP synthases. We also demonstrated that the two starting enzymes of de novo fatty acid biosynthesis, the acetyl-CoA synthetase and the acetyl-CoA carboxylase, are not affected by thiolactomycin.

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