title: Streptomyces cameroonensis sp. nov., a Geldanamycin Producer That Promotes Theobroma cacao Growth.
abstract: The taxonomy of an actinobacterial strain, designated JJY4T, was established using a polyphasic approach. JJY4Twas isolated from the rhizosphere of Chromolaena odorata in Yaoundé (Cameroon) during a project for the selection of biological control agents. Strain JJY4Texhibited antimicrobial activities against bacteria, fungi, and oomycetes. Strain JJY4Talso exhibited the traits of plant growth-promoting rhizobacteria such as the solubilization of inorganic phosphate, production of siderophores and indole-3-acetic acid, and 1-aminocyclopropane-1-carboxylate deaminase activity. In planta assays performed on cocoa plantlets confirmed that strain JJY4Texhibited strong abilities to promote plant growth and protect against Phytophthora megakarya, the main causal agent of cocoa pod rot. The formation of rugose-ornamented spores in spiral spore chains by strain JJY4Tis a typical feature of members found in the Streptomyces violaceusniger clade and, similar to some members of the clade, strain JJY4Tproduces geldanamycin. A phylogenetic analysis based on 16S rRNA gene sequences confirmed this classification and suggests that strain JJY4Tbe added to the subclade constituted of the type strains Streptomyces malaysiensis DSM 41697Tand Streptomyces samsunensis DSM 42010T. However, DNA-DNA relatedness and physiological characteristics allowed for the differentiation of strain JJY4Tfrom its closest phylogenetic relatives. Based on these results, strain JJY4T(=NRRL B-65369, =NBRC 112705) appears to represent a novel species in the S. violaceusniger clade for which the proposed name is Streptomyces cameroonensis sp. nov.
authors.affiliation: Laboratory of Phytoprotection and Valorization of Plants Resources, Biotechnology Centre-Nkolbisson.
authors.forename: Thaddée
authors.initials: T
authors.lastname: Boudjeko
authors.forename: Romaric Armel Mouafo
authors.initials: RA
authors.lastname: Tchinda
authors.forename: Mina
authors.initials: M
authors.lastname: Zitouni
authors.forename: Joëlle Aimée Vera Tchatchou
authors.initials: JA
authors.lastname: Nana
authors.forename: Sylvain
authors.initials: S
authors.lastname: Lerat
authors.forename: Carole
authors.initials: C
authors.lastname: Beaulieu
mesh_terms: D000890:Anti-Infective Agents / Q000378:metabolism*; D000898:Antibiosis; D015373:Bacterial Typing Techniques; D016227:Benzoquinones / Q000378:metabolism*; D002099:Cacao / Q000254:growth & development* / Q000382:microbiology*; D002163:Cameroon; D036604:Chromolaena / Q000382:microbiology; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D047029:Lactams, Macrocyclic / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D010838:Phytophthora / Q000254:growth & development; D010937:Plant Growth Regulators / Q000378:metabolism; D018517:Plant Roots / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013302:Streptomyces / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000890:Anti-Infective Agents; D016227:Benzoquinones; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D047029:Lactams, Macrocyclic; D010937:Plant Growth Regulators; D012336:RNA, Ribosomal, 16S; C001277:geldanamycin