CHEMICALLY MODIFIED TRANSFER RNA-DERIVED SMALL RNAs (tsRNAs) TO TARGET PATHOGENIC BACTERIA

1 . A chemically modified tsRNA comprising a nucleic acid sequence that is at least 80% identical to SEQ ID NO: 1 or SEQ ID NO: 2, at least 90% identical to SEQ ID NO: 1 or SEQ ID NO: 2, at least 95% identical to SEQ ID NO: 1 or SEQ ID NO: 2, or at least 98% identical to SEQ ID NO: 1 or SEQ ID NO: 2.

2 - 4 . (canceled)

5 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises a nucleic acid sequence of SEQ ID NO: 1 or SEQ ID NO: 2, or consists of a nucleic acid sequence of SEQ ID NO: 1 or SEQ ID NO: 2.

6 . (canceled)

7 . A chemically modified tsRNA comprising at least 15 consecutive nucleotides of any one of SEQ ID NO: 1 or SEQ ID NO: 2, at least 20 consecutive nucleotides of any one of SEQ ID NO: 1 or SEQ ID NO: 2, at least 25 consecutive nucleotides of any one of SEQ ID NO: 1 or SEQ ID NO: 2, or at least 27 consecutive nucleotides of SEQ ID NO: 1 or SEQ ID NO: 2.

8 - 10 . (canceled)

11 . A chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA is no more than 60 nucleotides in length, is no more than 50 nucleotides in length, no more than 40 nucleotides in length, or no more than 29 nucleotides in length.

12 - 14 . (canceled)

15 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA inhibits growth of F. nucleatum , or optionally induces death of F. nucleatum.

16 . (canceled)

17 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises a 2′ sugar substitution, wherein the 2′ sugar substitution is a 2′-fluoro substitution or a 2′-O-methyl substitution.

18 - 19 . (canceled)

20 . The chemically modified tsRNA of claim 17 , wherein the chemically modified tsRNA comprises at least one 2′-O-methylated nucleotide positioned at the 3′ end, two consecutive 2′-O-methylated nucleotides positioned at the 3′ end, or three consecutive 2′-O-methylated nucleotides positioned at the 3′ end.

21 . (canceled)

22 . The chemically modified tsRNA of claim 17 , wherein the chemically modified tsRNA comprises at least one 2′-O-methylated nucleotide positioned at the 5′ end, two consecutive 2′-O-methylated nucleotides positioned at the 5′ end, or three consecutive 2′-O-methylated nucleotides positioned at the 5′ end.

23 . (canceled)

24 . The chemically modified tsRNA of claim 17 , wherein the chemically modified tsRNA comprises three consecutive 2′-O-methylated nucleotides positioned at the 5′ end and three consecutive 2′-O-methylated nucleotides positioned at the 3′ end.

25 . The chemically modified tsRNA of claim 17 , wherein not all nucleotides of the chemically modified tsRNA are 2′-O-methylated.

26 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises a phosphorothioate internucleotide bond.

27 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises at least one phosphorothioate internucleotide bond at the 3′ end, or two consecutive phosphorothioate internucleotide bonds at the 3′ end.

28 . (canceled)

29 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises at least one phosphorothioate internucleotide bond at the 5′ end, or two consecutive phosphorothioate internucleotide bonds at the 5′ end.

30 . (canceled)

31 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises two consecutive phosphorothioate internucleotide bonds at the 3′ end and two consecutive phosphorothioate internucleotide bonds at the 5′ end.

32 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA comprises three consecutive 2′-O-methylated nucleotides positioned at the 5′ end, three consecutive 2′-O-methylated nucleotides positioned at the 3′ end, two consecutive phosphorothioate internucleotide bonds at the 3′ end, and two consecutive phosphorothioate internucleotide bonds at the 5′ end.

33 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA is AS38 or AS39.

34 . (canceled)

35 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA increases growth inhibition of Fusobacterium nucleatum (Fn) compared to a naturally occurring tsRNA with the same sequence.

36 - 37 . (canceled)

38 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA does not inhibit growth of Streptococcus mitis or Porphyromonas gingivalis.

39 . (canceled)

40 . The chemically modified tsRNA of claim 1 , wherein the chemically modified tsRNA is internalized by Fusobacterium nucleatum , such as strain 23726 or 25586.

41 - 42 . (canceled)

43 . A pharmaceutical composition, comprising at least one chemically modified tsRNA of claim 1 .

44 . A pharmaceutical composition, comprising two chemically modified tsRNAs: one is selected from AS38 and AS41, and the other one is selected from AS39 and AS42.

45 . The pharmaceutical composition of claim 44 , wherein the two chemically modified tsRNAs are AS38 and AS39 or AS41 and AS42.

46 - 53 . (canceled)

54 . A method of treating F. nucleatum infection or an F. nucleatum -associated disease, the method comprising administering to a subject at least one chemically modified tsRNA of claim 1 .

55 . The method of claim 54 , the method comprising administering to the subject two chemically modified tsRNAs: one is selected from AS38 and AS41, and the other one is selected from AS39 and AS42.

56 . The method of claim 54 , the method comprising administering to the subject two chemically modified tsRNAs: AS38 and AS39 or AS41 and AS42, or AS41 and AS42.

57 . (canceled)

58 . A method of treating F. nucleatum infection or a F. nucleatum -associated disease, the method comprising administering to a subject a pharmaceutical composition of claim 43 .

59 . (canceled)

60 . The method of claim 58 , the method comprising administering to the subject two chemically modified tsRNAs: one is selected from AS38 and AS41, and the other one is selected from AS39 and AS42.

61 . The method of claim 60 , the method comprising administering to the subject two chemically modified tsRNAs: AS38 and AS39 or AS41 and AS42.

62 - 63 . (canceled)

64 . The method of claim 58 , wherein the F. nucleatum -associated disease is a periodontal disease, a preterm birth issue, or a colorectal cancer.

65 - 68 . (canceled)

69 . The method of claim 54 , wherein the subject is a mammal.

70 . A method of killing Fusobacterium nucleatum , the method comprising contacting Fusobacterium nucleatum with at least one chemically modified tsRNA of claim 1 .

71 . The method of claim 70 , the method comprising contacting Fusobacterium nucleatum with two chemically modified tsRNAs: one is selected from AS38 and AS41, and the other one is selected from AS39 and AS42.

72 . The method of claim 70 , the method comprising contacting Fusobacterium nucleatum with two chemically modified tsRNAs: AS38 and AS39 or AS41 and AS42.

73 . (canceled)