Antibacterial activity of <i>Nocardia</i> spp. and <i>Streptomyces</i> sp. on multidrug-resistant pathogens causing neonatal sepsis

González-Nava, Janette Berenice; Manzanares-Leal, Gauddy Lizeth; Zapi-Colín, Luis Ángel; Dávila-Ramos, Sonia; Sandoval-Trujillo, Horacio; Ramírez-Durán, Ninfa

doi:10.1590/S1678-9946202466042

Acessibilidade / Reportar erro

Brasil

Revista do Instituto de Medicina Tropical de São Paulo

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

ORIGINAL ARTICLE • Rev. Inst. Med. trop. S. Paulo 66 • 2024 • https://doi.org/10.1590/S1678-9946202466042 copy

Antibacterial activity of Nocardia spp. and Streptomyces sp. on multidrug-resistant pathogens causing neonatal sepsis

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Neonatal sepsis leads to severe morbidity and occasionally death among neonates within the first week following birth, particularly in low- and middle-income countries. Empirical therapy includes antibiotics recommended by WHO. However, these have been ineffective against antimicrobial multidrug-resistant bacterial strains such as Klebsiella spp, Escherichia coli, and Staphylococcus aureus species. To counter this problem, new molecules and alternative sources of compounds with antibacterial activity are sought as options. Actinobacteria, particularly pathogenic strains, have revealed a biotechnological potential still underexplored. This study aimed to determine the presence of biosynthetic gene clusters and the antimicrobial activity of actinobacterial strains isolated from clinical cases against multidrug-resistant bacteria implicated in neonatal sepsis. In total, 15 strains isolated from clinical cases of actinomycetoma were used. PCR screening for the PKS-I, PKS-II, NRPS-I, and NRPS-II biosynthetic systems determined their secondary metabolite-producing potential. The strains were subsequently assayed for antimicrobial activity by the perpendicular cross streak method against Escherichia fergusonii Sec 23, Klebsiella pneumoniae subsp. pneumoniae H1064, Klebsiella variicola H776, Klebsiella oxytoca H793, and Klebsiella pneumoniae subsp. ozaenae H7595, previously classified as multidrug-resistant. Finally, the strains were identified by 16S rRNA gene sequence analysis. It was found that 100% of the actinobacteria had biosynthetic systems. The most frequent biosynthetic system was NRPS-I (100%), and the most frequent combination was NRPS-I and PKS-II (27%). All 15 strains showed antimicrobial activity. The strain with the highest antimicrobial activity was Streptomyces albus 94.1572, as it inhibited the growth of the five multidrug-resistant bacteria evaluated.

KEYWORDS
Neonatal sepsis; PKS; NRPS; Actinobacteria; Antimicrobial drug resistance

Strain code	Bacterial species	Type of sample	Age	Diagnosis of patient
Sec23	Escherichia fergusonii	Injury discharge	14 days	Injury with abscess
H793	Klebsiella oxytoca	Tracheal aspirate	21 days	Pneumonia
H1064	Klebsiella pneumoniae subsp. pneumoniae	Blood	21 days	Sepsis
H776	Klebsiella variicola	Blood	9 days	Sepsis
H759	Klebsiella pneumoniae subsp. ozaenae	Blood	12 days	Sepsis

Family	Antibiotic		Strains
		E. fergusonii Sec23	K. pneumoniae H1064	K. variicola H776	K. oxytoc a H793	K. pneumoniae subsp. ozaenae H759
Aminoglycosides	Amikacin
	Gentamicin
	Netilmicin
	Tobramycin
Monobactams	Aztreonam
Carbapenemics	Doripenem
	Ertapenem
	Imipenem
	Meropenem
Cephalosporins 1^st generation	Cefazolin
Cephalosporins 1^st generation	Cefaclor
Cephalosporins 2^nd generation	Cefotetan
Cephalosporins 2^nd generation	Cefuroxime
Cephalosporins 3^rd generation	Cefoperazone
	Cefotaxime	*	*
	Cefpodoxime
	Ceftazidime	*
	Ceftibuten
	Ceftriaxone	*	*
Cephalosporins 4^th generation	Cefepime
Cephalosporins 4^th generation	Ceftaroline
Cephalosporins 3^rd / inhibitor	Ceftazidime/avibactam
Cephalosporin 5^th / inhibitor	Ceftolozane/tazobactam
Fenicols	Chloramphenicol
Phosphonates	Fosfomycin
Glycylcyclines	Tigecycline
Nitrofurans	Nitrofurantoin
Penicillin	Ampicillin
Penicillin	Piperacillin
Penicillin/inhibitor	Amoxicillin/clavulanic acid
	Ampicillin/sulbactam
	Piperacillin/tazobactam
Polymyxins	Colistin
Quinolones 2^nd generation	Ciprofloxacin
Quinolones 3^rd generation	Levofloxacin
Sulfonamides	Trimethoprim/sulfamethoxazole
Tetracyclines	Tetracycline

Biosynthetic system	Primers	Amplicon size (bp)	PCR conditions	Electrophoresis conditions	Article
PKS-I	K1f(5’-TSAAGTCSAACATCGGBCA-3’) M6r (5’-CGCAGGTTSCSGTACCAGTA-3’)	1200–1400	Denaturation at 95 °C for 5 min, and 34 cycles of 95 °C for 30s, 55 °C for 2 min, 72 °C for 4 min, and 72 °C for 10 min	1.5% agarose gel, stained with ethidium bromide. Electrophoresis for 40 min at 120 V and 300µA	Ayuso-Sacido et al.¹⁸
PKS-II	KSα (5’-TSGRCTACRTCAACGGSCACGG-3’) KSβ (5’- TACSAGTCSWTCGCCTGGTTC-3’)	1000	Denaturation at 95 °C for 5 min, and 35 cycles of 95 °C for 30s, 58 °C for 20s, 72 °C for 4 min, and 72 °C for 10 min	1% agarose gel, stained with ethidium bromide. Electrophoresis for 40 min at 120 V and 300µA	Ayuso et al.¹⁹
NRPS-I	A3f (5’-GCSTACSYSATSTACACSTCSGG-3’) A7r (5’-SASGTCVCCSGTSCGGTAS-3’)	700–800	Denaturation at 95 °C for 5 min, and 35 cycles of 95 °C for 30s, 59 °C for 2 min, 72 °C for 4 min, and 72 °C for 10 min	1.5% agarose gel, stained with ethidium bromide. Electrophoresis for 40 min at 120 V and 300µA.	Ayuso-Sacido et al.¹⁸
NRPS-II	F(5’-CCGCCCATGGGTGCTCCGCGTGGCGAGCGGACCCGCGC-3’) R(5’-TGCCCCCTCGCCCTGGCCTCTAGATCC)	300	Denaturation at 95 °C for 5 min, and 40 cycles of 95 °C for 3 s, 63 °C for 45 s, 72 °C for 90s, and 72 °C for 10 min	2% agarose gel, stained with ethidium bromide. Electrophoresis for 30 min at 120 V and 300µA	Du and Shen²⁰
16S rRNA gen	8f (5’-AGAGTTTGATCMTGGCTCAG-3’) 1492R(5’-TACGGYTACCTTGTTACGACTT-3’)	1400–1500	Denaturation at 94 °C for 5 min, and 40 cycles of 94 °C for 1 min, 59 °C for 30s, 72 °C for 1 min, and 72 °C for 10 min	1% agarose gel, stained with ethidium bromide. Electrophoresis for 30 min at 120 V and 300µA	Yuan et al.²¹

Instituto de Medicina Tropical de São Paulo Av. Dr. Enéas de Carvalho Aguiar, 470, 05403-000 - São Paulo - SP - Brazil, Tel. +55 11 3061-7005 - São Paulo - SP - Brazil
E-mail: revimtsp@usp.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] Correspondence to:
Ninfa Ramírez-Durán Universidad Autónoma del Estado de México, Facultad de Medicina, Laboratorio de Investigación en Microbiología Médica y Ambiental., Av. Paseo Tollocan, C. Jesús Carranza, Moderna de la Cruz, Toluca Lerdo, 50180, Mexico E-mail: nramirezd@uaemex.mx