Diversity of pigmented Gram-positive bacteria associated with marine macroalgae from Antarctica.
Little is known about the diversity and roles of Gram-positive and pigmented bacteria in Antarctic environments, especially those associated with marine macroorganisms. This work is the first study about the diversity and antimicrobial activity of culturable pigmented Gram-positive bacteria associated with marine Antarctic macroalgae. A total of 31 pigmented Gram-positive strains were isolated from the surface of six species of macroalgae collected in the King George Island, South Shetland Islands. On the basis of 16S rRNA gene sequence similarities ≥99%, 18 phylotypes were defined, which were clustered into 11 genera of Actinobacteria (Agrococcus, Arthrobacter, Brachybacterium, Citricoccus, Kocuria, Labedella, Microbacterium, Micrococcus, Rhodococcus, Salinibacterium and Sanguibacter) and one genus of the Firmicutes (Staphylococcus). It was found that five isolates displayed antimicrobial activity against a set of macroalgae-associated bacteria. The active isolates were phylogenetically related to Agrococcus baldri, Brachybacterium rhamnosum, Citricoccus zhacaiensis and Kocuria palustris. The results indicate that a diverse community of pigmented Gram-positive bacteria is associated with Antartic macroalgae and suggest its potential as a promising source of antimicrobial and pigmented natural compounds.
Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile sleiva@uach.cl.
Sergio
S
Leiva
Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
Pamela
P
Alvarado
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Ying
Y
Huang
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Jian
J
Wang
Instituto de Ciencias Marinas y Limnológicas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
Ignacio
I
Garrido
D039903:Actinobacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology*; D000864:Antarctic Regions; D000890:Anti-Infective Agents / Q000494:pharmacology; D000898:Antibiosis; D004269:DNA, Bacterial / Q000235:genetics; D000068536:Bacillota / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D014644:Genetic Variation; D010802:Phylogeny; D010860:Pigments, Biological / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology; D012624:Seaweed / Q000382:microbiology*; D017422:Sequence Analysis, DNA
D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D010860:Pigments, Biological; D012336:RNA, Ribosomal, 16S
Actinobacteria; Antarctica; Gram-positive; antimicrobial activity; marine macroalgae; pigmented bacteria