Table 1 Summary of diverse MNPs biosynthesized by Shewanella and Geobacter species owning characteristic EET routes

Monometallic

 Au

Spherical NPs (~ 12 ± 5 nm), monodisperse and hydrophilic

S. oneidensis MR-1

Extracellular

Neither toxic nor inhibitory effect on Gram-negative and Gram-positive bacteria, high biocompatibility

[20]

Spherical NPs (~ 10 nm)

S. oneidensis MR-1

Cell surface

–

[66]

NPs (10–25 nm)

S. oneidensis MR-1

Cell surface and extracellular matrix

Partial repair of the damaged EET chain in S. oneidensis MR-1 mutant

[67]

Spherical NPs (3–11 nm)

S. putrefaciens CN32

Both intra- and extra cellular

–

[68]

Spherical NPs (10–30 nm)

S. haliotis (CTCC NO: M 2012444)

Extracellular

Size- and shape- dependent catalytic activity towards p-nitrophenol reduction

[69]

Spherical NPs (~ 15 nm)

Shewanella sp. CNZ-1

Cell surface

Catalytic activity towards 4-nitrophenol reduction

[70]

Spherical NPs (~ 20 nm)

G. sulfurreducens biofilm

Biofilm matrix

–

[24]

NPs (5–50 nm)

G. sulfurreducens biofilm

Cell surface and Biofilm matrix

In situ promotion of EET and electricity production

[73]

 Ag

Spherical NPs (2–11 nm, average 4 ± 1.5 nm), monodisperse

S. oneidensis MR-1

Extracellular

Bactericidal effect on Gram-negative and Gram-positive bacteria

[21]

NPs (5–35 nm)

S. oneidensis MR-1 (EPS)

Extracellular

–

[75]

Spherical NPs (8–10 nm)

S. oneidensis MR-1 (EPS)

Extracellular

–

[76]

NPs (40.9 nm for wild-type strain, 24.4 nm for△mtrC-omcA strain)

S. oneidensis MR-1

Extracellular

Size-dependent antibacterial effect

[77]

NPs (< 10 nm) grown on RGO

S. oneidensis MR-1

Extracellular

Catalytic degradation of 4-nitrophenol

[164]

 Pd

Nonuniform NPs

S. oneidensis MR-1

Cell surface

Catalytic degradation of polychlorinated biphenyl or perchlorate

[79, 80]

NPs (either < 10 nm or ~ 50 nm)

S. oneidensis MR-1

Periplasm or cell surface

–

[81]

NPs (25.8 ± 7.8 nm)

S. oneidensis MR-1

Cellular or outer-membrane

Size- and distribution-dependent catalytic degradations of nitrobenzene and p-chlorophenol

[165]

Nonuniform NPs ( 5–25 nm)

S. oneidensis MR-1

-

Catalytic reduction of 4-nitrophenol to 4-aminophenol

[22]

NPs (~ 13 nm)

S. oneidensis MR-1

Periplasm or cell surface

High catalytic activity towards oxygen reduction reaction

[166]

NPs (4–10 nm) without aggregation

S. loihica PV-4

Cell surface

High catalytic efficiency of Cr⁶⁺ reduction

[163]

NPs (6–8 nm) loaded on TiO₂ nanotubes

S. oneidensis MR-1

Extracellular

Photocatalytic degradation of methylene blue

[167]

Nonuniform NPs

G. sulfurreducens PCA

predominantly in the EPS matrix surrounding cells

–

[23]

NPs (5–15 nm)

G. sulfurreducens PCA

Cell surface or extracellular matrix when addition of AQDS

–

[82]

NPs

G. sulfurreducens (DSM 12127)

On cell surface

and inside the periplasm

Reduction of Cr⁶⁺ to Cr³⁺

[162]

 Se

Spherical NPs

S. oneidensis MR-1

Either in medium or attached to cell surface

–

[86]

Spherical NPs (~ 100 nm intracellularly, ~ 20 nm extracellularly)

S. oneidensis MR-1

Periplasmic space or cell surface

–

[87]

NPs (∼50 nm)

S. oneidensis MR-1

Extracellular matrix

–

[88]

Spherical NPs

S. oneidensis MR-1

Cell surface and extracellular matrix

–

[95]

Spherical NPs (181 ± 40 nm, 164 ± 24 nm)

Shewanella sp. HN-41

Extracellular

–

[89]

Nanowires and nanoribbons

Shewanella sp. HN-41

Extracellular

–

[90]

Spherical NPs (100–400 nm)

Shewanella sp. 9a

Both outside and inside the cells

–

[91]

Spherical NPs (50–100 nm)

G. sulfurreducens

Extracellular

[95]

NPs (251–350 nm for wild-type strain, < 150 nm for △extI strain)

G. sulfurreducens

Extracellular

[100]

 Te

Needle-like NPs

S. oneidensis MR-1

Either in cytoplasm or near cytoplasmic membrane

–

[86]

Needle-shaped nanorods (length of 100–200 nm, width of ~ 10 nm)

S. oneidensis MR-1

Periplasmic

and/or cytoplasmic spaces

–

[93]

Needle-shaped nanorods (length of 89–240 nm, width of 7.5–25 nm)

S. oneidensis MR-1

Extracellular

–

[94]

Spherical NPs under microaerobic

conditions while nanorods under aerobic conditions

Shewanella sp. Taa

Both outside and inside the cells

–

[91]

Nanorods (diameter of 8–75 nm)

S. baltica GUSDZ9 (Accession number: MF350629)

Intracellular

90% degradation of methylene blue dye and anti-biofilm activity against Gram-positive and Gram-negative human pathogens

[96]

 Cu

NPs (20–50 nm)

S. oneidensis MR-1

Predominantly intracellular

Catalyzing azide-alkyne cycloaddition (an archetypal “click chemistry” reaction)

[103]

NPs (10–16 nm) on CNT surfaces

S. oneidensis MR-1

Extracellular

Catalytic reduction of 4-nitrophenol to 4-aminophenol

[105]

NPs (10–16 nm) with polycrystalline nature and face centered cubic lattice

S. loihica PV-4

Both on cell surface and inside cells

High antibacterial against Escherichia coli

[104]

Bimetallic

 Pd/Au

Alloy NPs (6.61 nm)

S. oneidensis MR-1

On cell surface

High electrocatalytic activity and durability for ethanol and formic acid oxidation

[25]

 Pd/Pt

Small NPs (4.41 nm), flower-shaped NPs (59.90 nm)

S. oneidensis MR-1

On cell surface

Catalytic reduction of 4-nitrophenol (activity: bio-PdPt > Bio-Pd > Bio-Pt)

[26]

Alloy NPs (3–40 nm), polycrystalline and face-centered-cubic structure

S. oneidensis MR-1

Inside and outside the cells

High-efficient catalytic reduction of nitrophenol and azo dyes

[113]

 Pd/Ag

NPs on RGO

S. oneidensis MR-1

Extracellular

Catalytic reduction of 4- nitrophenol

[168]

Magnetite

 Magnetite (Fe₃O₄)

Spherical NPs (8–15 nm)

S. oneidensis

Extracellular

–

[120]

Spherical NPs (26.7–37.7 nm, average 28.8 ± 3.4 nm)

Shewanella sp. HN-41

Extracellular

–

[121]

Spherical NPs (4–6 nm)

S. piezotolerans WP3

Extracellular

–

[123]

NPs (20–30 nm)

G. sulfurreducens

Extracellular

Ferrimagnetic carrier supporting Pd-NPs for the Heck reaction coupling iodobenzene to ethyl acrylate or styrene

[125]

NPs (10–15 nm)

G. sulfurreducens

Extracellular

Reduction of Cr⁶⁺

[129]

 Co-doped magnetite (CoFe₂O₄)

Nanocrystals containing 23 atom% Co (16–8 nm)

G. sulfurreducens

Extracellular

An improved magnetic property

[132]

 Zn-doped magnetite (Zn_xFe_3-xO₄)

Spherical NPs (Zn-doping level dependent size)

G. sulfurreducens

Extracellular

An improved magnetic property

[127]

Metal chalcogenides

 As_xS_y

Filamentous nanotubes (diameter of 20–100 nm, lengths up to ~ 30 μm)

Shewanella sp. HN-41

Extracellular

Semiconductive and photoconductive

[29]

 As₂S₃

Nanofibers (diameter of 20–600 nm, length up to 150 μm)

Shewanella sp. ANA-3

Extracellular

–

[142]

 FeS

Nanosized colloids

S. loihica PV-4

Extracellular

Increased bioelectricity production

[143]

Nanowire clusters

S. oneidensis MR-1

Extracellular

Long-distance EET

[144]

Mackinawite

S. oneidensis MR-1

Extracellular

Accelerated dechlorination of trichloroethylene

[147]

NPs (30–90 nm)

S. oneidensis MR-1

Extracellular

Removal of aqueous Cr⁶⁺

[148]

NPs (~ 30 nm)

S. oneidensis MR-1

Both extracellular and intracellular

FeS-NPs biosynthesis coupling with naphthol green B biodegradation

[149]

 Ag₂S

NPs (53.4 nm for wild-type strain, 27.6 nm for△mtrC-omcA strain)

S. oneidensis MR-1

Extracellular

Catalytic reduction of methylviologen

[77]

Monodispersed and homogeneous spherical NPs (9 ± 3.5 nm)

S. oneidensis MR-1

Extracellular

Non-inhibitory and non-cytotoxic effect on bacteria and eukaryotic cell lines

[150]

 CuS

Homogenous NPs (∼5 nm), high hydrophility and stablity

S. oneidensis MR-1

Extracellular

Photothermal agent

[152]

Hollow CuS nano/micro shell (diameter of 17.4 nm, length of 80.8 nm)

S. oneidensis MR-1

On cell surface

Cr⁶⁺ removal

[153]

 ZnS

Spherical NPs (~ 5 nm)

S. oneidensis MR-1

Extracellular

Photodegradation of rhodamine B

[154]

 Mn:ZnS

Nano quantum dots (5–10 nm)

S. oneidensis JG3631

Extracellular

–

[155]

 CdS

NPs (15 nm)

S. oneidensis MR-1

Extracellular

Increased cytotoxic effect on brain cancer cell lines

[158]

NPs (4.5–11.5 nm, average 7 nm)

S. oneidensis MR-1

On cell surface

Photoreductive degradation of trypan blue

[159]

NPs

G. sulfurreducens PCA

On cell surface

Light-driven bio-decolorization of methyl orange

[30]

 CdSe

Ultrafine NPs (3.3 ± 0.6 nm)

S. oneidensis MR-1

Inside cytoplasm

Yellow fluorescence

[160]

 HgSe

Monodispersed NPs (4.3 ± 0.79 nm)

S. putrefaciens 200

On cell surface

–

[169]